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June 24, 2008

Barclays Capital iPath Barclays Capital Global Carbon Index Guide May 2008

BGCI: A Carbon Investment Benchmark The Barclays Capital Global Carbon IndexTM “BGCI” measures the performance of the most liquid carbon-related credit plans and is designed to be an industry benchmark for carbon investors. Each plan included in the index is represented by the most liquid instrument available in the marketplace. The index expects to incorporate new plans as they develop around the world. At inception the index includes two plans: ??EU ETS Phase II; and ??Kyoto Clean Development Mechanism (CDM). The index is published in EUR and USD as excess return and total return indices. Each component plan is also available expressed in EUR and USD as excess and total return indices. Figure 1: BGCI And Component Total Return Indices In USD 190 BGCI USD TR 170 EUA TR USD CER TR USD Index USD 150 130 Total Retrun 110 90 70 Nov 06 Feb 07 May 07 Aug 07 Nov 07 Feb 08 May 08 Source: Barclays Capital Reducing Greenhouse Gas Emissions The climate debate is now focused on how best to reduce emissions The rise in global temperatures and atmospheric carbon dioxide concentrations, coupled with the recent spate of extreme weather events, has changed the focus of the climate change debate. The question now, is not whether to, but rather how best to, reduce greenhouse gas (GHG) emissions on a global scale. The international response to climate change has centered on the Kyoto protocol The international response so far has centered on the Kyoto protocol (“Kyoto”), an international agreement that requires the developed nation signatories to abate their GHG emissions by an average of 5.2% over 2008-12 relative to 1990. The GHGs that Kyoto addresses are carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulphur hexafluoride. Most significantly the protocol put in place various “flexible trading mechanisms” to assist the countries with emissions reduction targets to achieve their goals at the lowest possible cost. One of the trading mechanisms is the Clean Development Mechanism (CDM), a project-based initiative whereby developing nations can implement projects to reduce GHGs and receive Certified Emission Reduction credits (CERs) for each tonne of carbon dioxide equivalent avoided. Barclays Capital Index Products 1

In order to achieve the Kyoto targets, a variety of regional and national policies exist aimed at abating GHG emissions. These include policy measures such as taxation of emissions, legislation or implementation of Cap & Trade plans. Cap & Trade is fast becoming the preferred policy instrument for controlling emissions Cap & Trade is fast becoming the preferred policy instrument for controlling GHG emissions. A Cap & Trade mechanism sets emission limits (ie, the right to emit a certain quantity of emissions), which can be allocated or auctioned to the parties in the plan up to the total emissions cap. The cap is set at a level that would achieve the required reduction. The parties are then able to trade their emission rights freely among themselves. In theory the “trade” element allows emission abatement to take place at the lowest possible cost by allowing companies with a high marginal abatement cost to buy credits from companies that can abate GHG emissions for less. The “cap” is best for the environment as it places a firm limit on emissions that would be unlikely to be achieved via taxation. Cap & Trade is not a new concept. Indeed, it has an impressive track record abating sulphur dioxide and nitrogen oxides through a variety of regional US plans over the past 15 years, resulting in a 40% reduction in sulphur dioxide in the US North East since 1995. The adoption of Cap & Trade as the primary method for curbing GHGs began fairly recently with a plan in Denmark in 2001. The European Union Emissions trading scheme has become the Since then, national or regional Cap & Trade plans have been (or are shortly to be) introduced in the European Union, Japan, the US, Australia and New Zealand. The European Union Emissions trading scheme (EU ETS) was launched in 2005 and has become the largest largest greenhouse gas trading plan in the world GHG trading plan in the world. The EU ETS has entered Phase II (2008-12), following the initial “trial” first Phase (2005-07). In 2008, New Zealand will be launching its GHG Cap & Trade plan, which may at some stage link with an Australian plan. The US is due to launch a state-level GHG Cap & Trade plan, the Regional Greenhouse Gas Initiative (RGGI), in 2009. There are also several other state level plans at the planning stage, which may prove to be the precursor for a federal Cap & Trade plan by 2012. 2 Index Products Barclays Capital

Tradable Carbon Credits EUAs and CERs are the most liquid and tradable emission credits. The following table sets out the key carbon credits that are traded around the world. Figure 2: Tradable Carbon Credits Traded volume (MtCO2e) Asset Description Usage 2006 2007 (est) Trading platform Assigned Amount Units (AAUs) AAUs are tradable emissions units equalling 1 tonne CO2 equivalent (CO2e). They are allocated under Kyoto for each commitment period. Each country is permitted to emit greenhouse gases equivalent to their assigned amount. Governments—- OTC European Union Allowances (EUAs) EUAs are allocated under the National Allocation Plan of each country within the European Union Emission Trading Scheme (EU ETS). Each EUA represents one tonne of CO2 (other GHGs are not yet included in the EU-ETS). Companies 1,101 2,337 Exchange traded & OTC Certified Emission Reductions (CERs) A CER is a tradable credit worth one tonne of CO2e generated by projects accredited by the Clean Development Mechanism (CDM) of the Kyoto Protocol. These are aimed at the developing world to encourage carbon abatement and generate revenue. There are two types of CERs that are traded—primary and secondary. Governments & companies Primary CERs are classified as CERs purchased on a forward basis directly from a CDM project prior to the CERs being issued by the UN. Primary CERs carry project delivery risk and are therefore valued at a discount to secondary CERs. 450 570 Exchange traded & OTC Secondary CERs represent credits which are either issued by the UN and traded in the spot or forward market, or forward CERs where the volume is guaranteed and therefore there is no project delivery risk. 25 200 Emission Reduction Units (ERUs) ERUs are credits allocated to projects under the Joint Implementation (JI) provisions of Kyoto and are each worth one tonne of CO2e. JI projects take place within Kyoto-capped countries only. Governments & companies 16—OTC Removal Units (RMUs) RMUs are carbon offsets allocated for carbon sink projects involving land use, land use change and forestry. Governments (companies can, but unlikely)—- OTC Voluntary Emission Reductions (VERs) VERs are carbon offsets offered by commercial firms whereby the purchaser pays to have an emissions allowance purchased and retired on their behalf to offset the carbon. Companies 13 25 OTC Carbon Financial Instrument (CFI) CFIs are traded on a voluntary basis on the Chicago Climate Exchange (CCX). Each CFI represents 100 tonnes of CO2e. Companies 10 20 Exchange traded New South Wales Greenhouse Gas Reduction Scheme (GGAS) GGAS establishes annual state-wide GHG reduction targets, and then requires individual electricity retailers and certain other parties which buy or sell electricity in NSW to meet mandatory benchmarks based on the size of their share of the electricity market. Companies 20 22 Exchange Forthcoming credits Regional Greenhouse Gas Initiative (RGGI) Western Climate Initiative (WCI) California New Zealand Australia National Emissions Trading Scheme Companies na na na Source: UNFCCC, World Bank, New Carbon Finance, European Commission, Barclays Capital Barclays Capital Index Products 3

Background On The EU ETS EU ETS covers 12,000 industrial installations generating CO2 emissions across the EU The EU Emission Trading Scheme is a Cap & Trade plan that covers approximately 12,000 industrial installations generating CO2 emissions in certain sectors, such as power generation, utilities, iron, steel, and cement. Under the EU ETS, each country has a National Allocation Plan (NAP), which determines the caps on GHG emissions for each installation. Installations are allocated allowances (EUAs) up to their cap or, in Phase II of the plan, may purchase a proportion through auction. Installations have to monitor their emissions and after each year submit EUAs equivalent to their verified emissions. Companies that do not have sufficient EUAs can buy them from other EC companies that have a surplus, or within certain limits, use CERs and/or ERUs for compliance purposes instead of EUAs. The EU ETS Phase I runs from 2005-07, Phase II from 2008-12 and Phase III commences in 2013 The EU ETS began with a first Phase running from 2005-07. Looking back, Phase I will chiefly be remembered for the price collapse in spring 2006 when the publication of 2005 verified emissions data showed that the market was long allowances and not short as previously thought. The surplus was due to over allocation of credits in the order of around 5% of the total cap. Phase II of the plan is in line with the first Kyoto period and runs from 2008-12. Compared to the first phase, allocations in the second phase have been reduced to ensure that they are consistent with meeting the national Kyoto targets. The annual shortfall of credits will be approximately 285 million tonnes (source: New Carbon Finance). In addition, EU legislation enables banking of credits from Phase II to Phase III (this was not possible between Phase I and Phase II), which is expected to provide further price support for Phase II credits. Phase III will commence in 2013. Pricing of allowances is driven by supply and demand. The main factors determining demand are the weather and relative fuel prices As in any market, EUA pricing is set by supply and demand. Supply is determined by allowances (EUAs) and other carbon credits that are available to the market, eg, CERs and ERUs. Demand is determined by the volume of carbon emitted during the year in relation to the annual allocation. The main factors influencing volumes emitted in the short term are the weather, relative fuel prices and the amount of electricity generated from non fossil fuel sources. The effect of weather has been felt at various times in the EUA market, most notably in winter 2006 when cold weather and a shortage of gas drove up Phase I prices, and in January 2007, when there was the opposite effect. Technically, these factors should only have affected Phase I prices, but in January 2007 market sentiment also caused Phase II prices to soften. Figure 3: Exchange-Traded Volumes EU ETS In 2006 (mtCO2) Powernext EEX 6% 2% Nord Pool 11% ECX 81% Source: Exchanges, IFSL 4 Index Products Barclays Capital

Trading of allowances is concentrated on the European Climate Exchange The bulk of exchange trading activity in EUAs is concentrated on the European Climate Exchange (ECX) CFI contracts that are traded on the ICE Futures exchange in London. In 2006, ECX accounted for over 80% of EU ETS exchange transactions (including OTC contracts cleared through exchanges) with the balance traded on Nord Pool, Powernext and the European Energy Exchange. Background On CDM CDM is a project based initiative for developing nations. CDM projects generate CERs CDM is a project-based initiative whereby signatories of Kyoto without an emissions reduction target (ie, developing nations such as India, China and Brazil) can implement projects to reduce GHGs and receive CERs for each tonne of CO2 equivalent avoided. In order to receive CERs, a CDM project must first be registered with the United Nations Framework Convention on Climate Change (UNFCCC) Secretariat. To be registered, a project must be approved by the host country and must go through a strict set of procedures to show that it meets the CDM eligibility requirements. Around 850 projects have been registered so far, and more than 2,600 more projects are in the pipeline. Once a project has been registered, it must monitor its emission reductions and have them verified by an independent UN-accredited organization. The verified monitoring reports are subsequently reviewed by the UNFCCC Secretariat in advance of actual CER issuance. Approximately 94 million CERs have been issued so far. Figure 4: CDM Projects Share Of Volume Supplied In 2006 Africa Other 3% 7% Rest of Asia 7% Rest of L.America 6% Brazil 4% China India 61% 12% Source: World Bank The market for CERs includes Governments, EU ETS buyers and companies operating under voluntary plans CERs may be used by governments to supplement AAU holdings to meet Kyoto obligations. They may also be used by companies operating within GHG trading plans which recognize such credits (eg, the EU ETS, the Regional Greenhouse Gas Initiative in the US, the Japanese Voluntary Emission Trading Scheme). Of the three “flexible trading mechanisms” of Kyoto, the CDM shows the most market activity. Investing In Environmental Markets Investment in carbon funds tops $12.5bn to date Since 2001, there has been a marked increase in the amount invested in the environmental markets. Currently $12.5bn has been invested in carbon funds. In addition, clean energy projects have attracted $75.4bn worth of investments in 2006, compared to $54.2bn in 2005 (sources: New Energy Finance and Bloomberg). Barclays Capital Index Products 5

Investors may have been attracted into these markets for the following reasons: ??The perceived consensus that the global carbon price could rise significantly if the worst-case scenarios of climate change are to be avoided ??Portfolio diversification ??Hedge on industrial and energy prices ??Ethical investment Figure 5: Cumulative Investments In Carbon Funds (US$ bn) 14 12.5 billion) 12 $ 10 8.0 8 in carbon funds (US 6 4.8 4 investment 2.7 1.7 2 0.8 0.3 0 2001 2002 2003 2004 2005 2006 2007 Source: New Carbon Finance Trading in carbon credits has grown significantly in 2006 and 2007 In addition to the growth in investments in carbon funds, the GHG trading markets have witnessed significant growth. For example, in 2006 the carbon market grew threefold to $30bn and by 2020 the global carbon market could increase to $700bn (source: New Carbon Finance). Figure 6: Global Carbon Markets, Volumes Traded 3500 CER 3000 EU ETS 770 2500 2000 1500 450 2337 1000 Volume traded, million tonnes CO2 500 341 1101 321 0 2004 2005 2006 2007 Est Note: CER volume includes primary and secondary volume Source: World Bank, New Carbon Finance, Barclays Capital 6 Index Products Barclays Capital

The Index The Barclays Capital Global Carbon IndexTM “BGCI” measures the performance of the most liquid carbon-related credit plans and is designed to be an industry benchmark for carbon investors. Each plan included in the index is represented by the most liquid instrument available in the market place. At inception the index includes two plans: ??EU ETS Phase II; and ??Kyoto Clean Development Mechanism (CDM). The index will incorporate new plans as they develop around the world. Eligible plans, index weights and carbon instruments are determined annually by the index sponsor (Barclays Capital) with the approval of the independent Barclays Environmental Markets Index Committee. The target weights are implemented during the annual roll of the index, which takes place each November. The index sponsor with the approval of the index committee may also adjust the index composition quarterly to take account of market developments. The index will be published in EUR and USD as excess return and total return indices. Indices for each component plan are also available in EUR and USD as excess and total return indices. Figure 7: Barclays Capital Global Carbon Index Structure Global Carbon Index EU Emissions Trading Kyoto Clean Development Other schemes as they Scheme Phase II. Mechanism. become eligible … Plan European Union Certified Emission Allowance (EUA). Reduction (CER). Instrument Futures Contract traded Futures contract traded on European Climate on European Climate Exchange (ECX) Exchange (ECX) carbon Source: Barclays Capital The Barclays Capital Environmental Markets Index Committee Barclays Capital has set up an independent committee to approve the rules, composition and methodology of its environmental markets indices including the BGCI. The committee will also provide governance over the quality of the indices and consider any issues involving any discretionary decisions related to the index. The committee currently consists of three members from Barclays Capital and five independent carbon market professionals and individuals from the institutional investor community. Barclays Capital Index Products 7

Barclays Capital Global Carbon IndexTM Facts And Figures Figure 8: Barclays Capital Global Carbon Total Return Index TM BGCI Total Return Indices (USD) BGCI Monthly Total Returns (USD) 190 25 BGCI USD TR BGCI (USD) 20 170 EUA TR USD (%) 15 CER TR USD Return 10 150 Index USD 5 Retrun 130 Total 0 -5 Monthly 110 -10 Total -15 90 -20 70 Jan 07 Feb 07 Apr 07 Jun 07 Sep 07 Oct 07 Dec 07 Jan 08 Feb 08 Apr 08 Nov 06 Feb 07 May 07 Aug 07 Nov 07 Feb 08 May 08 Nov 06 Dec 06 Mar 07 May 07 Jul 07 Aug 07 Nov 07 Mar 08 Annualized USD Index Returns By Component BGCI 2007-08 Target Weights BGCI USD EUA USD CER USD Kyoto CDM 20% Annualized total return 35.8% 39.5% 21.4% Annualized volatility 34.8% 37.2% 28.7% Sharpe ratio 1.01 1.06 0.69 EU ETS Phase II Source: Barclays Capital Figure 9: Monthly BGCI USD Total Returns (%) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec BGCI 2006 16.9 0.6 2007 -14.8 -1.6 16.0 7.4 21.1 -3.0 -2.9 -6.5 10.4 10.4 1.6 -1.3 2008 - -14.1 12.7 0.5 9.1 BGCI EUA 2006 18.6 0.4 2007 -15.8 -2.3 17.9 9.2 21.5 -2.7 -4.8 -7.9 12.1 12.1 1.2 -0.3 2008 -13.7 12.7 1.4 9.9 BGCI CER 2006 9.8 1.5 2007 -10.9 1.0 8.5 -0.3 19.0 -4.1 6.3 -0.1 3.4 3.4 3.2 -5.3 2008 -15.8 13.0 -3.5 5.6 Source: Barclays Capital 8 Index Products Barclays Capital

Figure 10: Barclays Capital Global Carbon EUR Total Return Index Annualized EUR Index Returns By Component BGCI Monthly Total Returns (EUR) BGCI EUR EUA EUR CER EUR 25 BGCI (EUR) Annualized total return 34.8% 38.5% 20.6% 20 (%) Annualized volatility 34.7% 37.2% 28.6% 15 Return Sharpe ratio 1.01 1.05 0.68 10 5 Total 0 -5 Monthly -10 -15 -20 Nov 06 Dec 06 Jan 07 Feb 07 Mar 07 Apr 07 May 07 Jun 07 Jul 07 Aug 07 Sep 07 Oct 07 Nov 07 Dec 07 Jan 08 Feb 08 Mar 08 Apr 08 Source: Barclays Capital Figure 11: Monthly BGCI EUR Total Returns (%) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec BGCI 2006 16.7 0.5 2007 -15.0 -1.7 15.7 7.3 20.9 -3.0 -2.9 -6.5 10.3 10.3 1.5 -1.3 2008 -14.1 12.8 0.7 9.3 BGCI EUA 2006 18.4 0.3 2007 -15.9 -2.4 17.6 9.1 21.3 -2.8 -4.8 -8.0 12.1 12.1 1.1 -0.4 2008 -13.7 12.7 1.7 10.1 BGCI CER 2006 9.6 1.3 2007 -11.1 0.9 8.3 -0.4 18.8 -4.2 6.3 -0.2 3.4 3.4 3.1 -5.2 2008 -15.8 13.0 -3.3 5.8 Source: Barclays Capital Additional Information The index is calculated daily in EUR and USD for London and Target business days, and published with one day lag on the web http://www.barcap.com/indices/ and on Bloomberg. Figure 12: Bloomberg Tickers For The BGCI And Sub-Indices Index USD total return USD excess return EUR total return EUR excess return BGCI BXIIGCUT BXIIGCUP BXIIGCET BXIIGCEP BGCI EUA BXIIEAUT BXIIEAUP BXIIEAET BXIIEAEP BGCI CER BXIICEUT BXIICEUP BXIICEET BXIICEEP Source: Barclays Capital Barclays Capital Index Products 9

BARCAP_RESEARCH_TAG_FONDMI2NBUR7SWED Index Methodology General Principles And Selection Process The BGCI has been designed to provide exposure to the global price of carbon. To achieve this, the index will reference the world’s major carbon-related credit plans. As at May 2008, the index includes the EU ETS, which is the most developed Cap & Trade carbon plan, and the Kyoto Protocol’s Clean Development Mechanism, which has global reach. It is expected that different regions around the world will develop their own carbon trading plans. If and when any of these become sufficiently robust and represent a material proportion of the global carbon market, as determined by the index sponsor, they will be considered for inclusion in the index reference plans. The financial exposure of the index is equivalent to holding a basket of carbon instruments. The secondary market for carbon instruments is mainly based on futures contracts traded on exchange and forward contracts traded on an OTC basis. The objective of this index will be to invest in futures, which give a daily mark to market of the spot price of the underlying forward, but, in cases where this is not possible, eg, in the secondary CER market prior to march 2008, the index will instead gain exposure through a forward contract provided transparent pricing is available. Selection Of Carbon Instrument For Plans Included In The Index The index references one underlying carbon instrument per plan. The carbon instrument selected will be that which, in the view of the index sponsor, is the most appropriate and reflective of traded volume and provides accurate daily pricing. If a carbon instrument is available in both the forward and futures markets, the future will generally be preferred, provided, in the view of the index sponsor, it is suitably liquid and has accurate and reliable pricing. Where a carbon instrument is traded on more than one futures exchange, the index will select the contract with the highest traded volume. Determination Of Annual Weights The weight of each plan included in the index is determined annually by the index sponsor in discussion with the independent index committee. Plan weights are designed to reflect the financial value of trading in the underlying carbon credits. The weights will take into account the past years trading volume both on exchange and OTC (where data is available) together with expected future volumes. Quarterly Composition Adjustments The index sponsor with the approval of the index committee may also adjust the index composition quarterly to take account of market developments. Figure 13: Index Composition at May 2008 Current Hedging Price Quote Target GHG Credit Plan Instrument Underlying Currency Price Source Weight EU ETS Phase II ECX EUA Future Dec 2008 European Union Allowance EUR ECX closing settlement price 80% Kyoto CDM ECX CER Future Dec 2008 Certified Emission Reduction EUR ECX closing settlement price 20% Source: Barclays Capital 10 Index Products Barclays Capital

BARCAP_RESEARCH_TAG_FONDMI2NBUR7SWED Index Calculation Methodology The index is implemented using a market-standard commodity index methodology described below. As current index components are all priced in EUR, the index formulae shown below are all expressed in EUR except where noted. Pricing For listed futures the index will use the official exchange settlement price. For CER forward contracts, prices have been sourced as follows: ??October 2006 – March 2007, Barclays Capital ? March 2007 – April 2008, Reuters CER Index, as published on: www.reutersinteractive.com/CarbonPrices FX rates used in the calculation of the USD indices are the 4pm London close mid-spot rates published by WM Company on Bloomberg page WMCO. Notation For variables that are affected by the index roll, the “next” instance is marked with a prime, eg, for variable x: this period x, next period x’ Price of first nearby contract k at time t Pk,t ‘ Price of second nearby contract k at time t P k,t IH Index holdings of first nearby contract k k IH ‘ Index holdings of second nearby contract k k Contract weight of first nearby contract k on day t CWk,t CW ‘ Contract weight of second nearby contract k on day t k,t IPWk Fixed percentage basket weight for commodity k Index Holdings And Re-Balancing The index replicates a fund of commodity futures (and/or forwards), which are re- weighted periodically back to fixed percentage weights. The primary re-weighting of the index will take place annually each November. On the last day of October (the determination date), index holdings are determined for each carbon instrument. These index holdings are calculated based on fixed percentage basket weights and contract prices on the close of that day. IH =IPW ×IndexNotionalValue / P k k k,t Roll of commodity futures/forwards takes place over the five business days after the determination date with amounts rolled equally over the period. Figure 14: At Inception The Futures/Forward Schedule Will Be: Plan Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec EUA Z Z Z Z Z Z Z Z Z Z Z Z+1 CER Z Z Z Z Z Z Z Z Z Z Z Z+1 Note: Z:: Dec, Z+1: Dec in subsequent year. Source: Barclays Capital Barclays Capital Index Products 11

BARCAP_RESEARCH_TAG_FONDMI2NBUR7SWED Note that the first delivery year for the two plans included at inception is 2008. In the absence of a 2007 contract, the December 2008 contract has been used. Index Weighted Value Each day the index has an index weighted value. On a non roll day the index weighted value is as follows: IWVt ?IH * P =k k k,t On days when there is a roll, the index weighted value is given by: IWVt =?IH * CW * P +?IH ‘ * CW ‘ * P’ k k k ,t k,t k k k t , k,t Note that IH = IH ‘ unless the index is re-weighted or the weights reset. k k Daily Commodity Weights Each day the weight of a commodity ( DCW k,t ) in the index is given by: IH * CW * P + IH ‘ * CW ‘ * P’ k k ,t k, t k k ,t k,t DCW = k,t IWV t Daily Price Return Daily returns ( DRt ) are calculated based on index holdings from the previous day: ?IH * CW * P + ? IH ‘ * CW ‘ * P’ k k k ,t 1 k,t k k k,t 1 k,t DRt = ( ) ( 1 ) ?IH * CW * P +? IH ‘ * CW ‘ * P’ k k k,t 1 k,t 1 k k k ,t 1 k,t 1 Day after the contract roll is finished (ie, CW ‘ = 100%) IH takes value from k,t 1 k IH ‘ the day before. k Note that on a non-roll day CW = 100%, CW ‘ = 0% and IH = IH ‘ k ,t 1 k ,t 1 k k Therefore DRt simplifies to: ?IH * P k k k,t DRt = ( ) 1 ?IH * P k k k,t 1 Excess Return Index An index of daily excess returns is created starting at 100 on 31 October 2006. It is called an excess return index because it gives you the excess over the return you get from the collateral used to purchase contracts. The excess return index is calculated as follows: ERIt =ERI * (1 + DR t ) t 1 The index is rounded to four decimal places. The excess return index is also available in USD and has a base of 100 on 31 October 2006. The index is calculated as follows: USD _ ERIt =USD _ ERI 1 + DRt FXt FX t 1 t 1 Where: FXt is the EUR to USD FX rate on day t. 12 Index Products Barclays Capital

BARCAP_RESEARCH_TAG_FONDMI2NBUR7SWED Note that the first delivery year for the two plans included at inception is 2008. In the absence of a 2007 contract, the December 2008 contract has been used. Index Weighted Value Each day the index has an index weighted value. On a non roll day the index weighted value is as follows: IWVt ?IH * P =k k k,t On days when there is a roll, the index weighted value is given by: IWVt =?IH * CW * P +?IH ‘ * CW ‘ * P’ k k k ,t k,t k k k t , k,t Note that IH = IH ‘ unless the index is re-weighted or the weights reset. k k Daily Commodity Weights Each day the weight of a commodity ( DCW k,t ) in the index is given by: IH * CW * P + IH ‘ * CW ‘ * P’ k k ,t k, t k k ,t k,t DCW = k,t IWV t Daily Price Return Daily returns ( DRt ) are calculated based on index holdings from the previous day: ?IH * CW * P + ? IH ‘ * CW ‘ * P’ k k k ,t 1 k,t k k k,t 1 k,t DRt = ( ) ( 1 ) ?IH * CW * P +? IH ‘ * CW ‘ * P’ k k k,t 1 k,t 1 k k k ,t 1 k,t 1 Day after the contract roll is finished (ie, CW ‘ = 100%) IH takes value from k,t 1 k IH ‘ the day before. k Note that on a non-roll day CW = 100%, CW ‘ = 0% and IH = IH ‘ k ,t 1 k ,t 1 k k Therefore DRt simplifies to: ?IH * P k k k,t DRt = ( ) 1 ?IH * P k k k,t 1 Excess Return Index An index of daily excess returns is created starting at 100 on 31 October 2006. It is called an excess return index because it gives you the excess over the return you get from the collateral used to purchase contracts. The excess return index is calculated as follows: ERIt =ERI * (1 + DR t ) t 1 The index is rounded to four decimal places. The excess return index is also available in USD and has a base of 100 on 31 October 2006. The index is calculated as follows: USD _ ERIt =USD _ ERI 1 + DRt FXt FX t 1 t 1 Where: FXt is the EUR to USD FX rate on day t. 12 Index Products Barclays Capital

BARCAP_RESEARCH_TAG_FONDMI2NBUR7SWED Index Basket The Barclays Capital Environmental Markets Index committee met in April 2008 to review the carbon instruments used in the index. Since the BGCI was launched, CER futures have been listed on several exchanges and the committee voted to use ECX CER futures prices in the index from May 2008. The change was effected over the first five business days in May, and the index weights were unaffected. Figure 15: Contracts Included In The Index From Nov 2006 With Initial Index Period Weights Annual Plan Carbon Instrument Weight Price Source Nov 2006 to Oct 2007 EUA ECX EUA Dec 2008 future 80.0% ECX CER CER Dec 2008 forward 20.0% Barclays Capital/Reuters CER index From Nov-2007 to April 2008 EUA ECX EUA Dec 2008 future 80.0% ECX CER CER Dec 2008 forward 20.0% Reuters CER Index From May 2008 (Quarterly index adjustment) EUA ECX EUA Dec 2008 future 80.0% ECX CER ECX CER Dec 2008 future 20.0% ECX Note: Actual weights for May 2008 were EUA 82.2%, CER 17.8% Source: Barclays Capital Market Disruption Market disruption occurs whenever there is no tradable price available for an index component. This might be because of a failure of an exchange to publish a final futures settlement price, a failure to obtain the reference price for a forward contract used in the index, or the publication of a “limit” price by an exchange. Market disruption will be determined by the index sponsor at its sole and absolute discretion. The BGCI uses standard commodity index conventions for handling market disruptions and determining reference prices. If a market disruption event occurs during the roll period of a specific contract, then the contract weight CW and CW’ and prices for that contract remain the same as the previous day. On the first day that there is no disruption for that contract, the contract weights “catch up”. For example, if there is no market disruption in EUA on the first day of roll, then CW is 80% and CW’ is 20%. If there are market disruptions on the second, third and fourth day, then CW and CW’ remain the same as on the first day of the roll, and on the fifth day of the roll CW becomes 0% and CW’ becomes 100%. If the market disruption exists on the last day of the roll, then the roll for a given contract resumes on the next business day free of market disruption. To avoid doubt, in the event of market disruption in specific contracts, the roll is delayed for those contracts only. Unaffected contracts roll as normal. 14 Index Products Barclays Capital

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An investment in iPath ETNs involves risks, including possible loss of principal. For a description of the main risks see “Risk Factors” in the applicable prospectus. Barclays Bank PLC has filed a registration statement (including a prospectus) with the SEC for the offering to which this communication relates. Before you invest, you should read the prospectus and other documents Barclays Bank PLC has filed with the SEC for more complete information about the issuer and this offering. You may get these documents for free by visiting www.iPathETN.com or EDGAR on the SEC website at www.sec.gov. Alternatively, Barclays Bank PLC will arrange for Barclays Capital Inc. to send you the prospectus if you request it by calling toll-free 1-877-76-iPATH, or you may request a copy from any other dealer participating in the offering. Barclays Global Investors Services, a subsidiary of Barclays Global Investors, N.A. (“BGINA”), assists in the promotion of the Securities. Barclays Global Investors, N.A. and Barclays Capital Inc. (“BCI”) are affiliates of Barclays Bank PLC. iPath ETNs (the “Securities”) are unsecured obligations of Barclays Bank PLC and are not secured debt. The Securities are riskier than ordinary unsecured debt securities and have no principal protection. Risks of investing in the Securities include limited portfolio diversification, trade price fluctuations, uncertain principal repayment, and illiquidity. Investing in the Securities is not equivalent to direct investment in index or index components. The investor fee will reduce the amount of your return at maturity or on redemption, and as a result you may receive less than the principal amount of your investment at maturity or upon redemption of your Securities even if the value of the relevant index has increased. An investment in iPath ETNs may not be suitable for all investors. The Securities may be sold throughout the day on the exchange through any brokerage account. There are restrictions on the minimum number of Securities you may redeem directly with the issuer as specified in the applicable prospectus. Commissions may apply and there are tax consequences in the event of sale, redemption or maturity of Securities. Sales in the secondary market may result in significant losses. BGINA and its affiliates, and BCI and its affiliates do not provide tax advice and nothing contained herein should be construed to be tax advice. Please be advised that any discussion of U.S. tax matters contained herein (including any attachments) (i) is not intended or written to be used, and cannot be used, by you for the purpose of avoiding U.S. tax-related penalties; and (ii) was written to support the promotion or marketing of the transactions or other matters addressed herein. Accordingly, you should seek advice based on your particular circumstances from an independent tax advisor. An investment in iPath ETNs linked to the performance of the Barclays Capital Global Carbon Index Total ReturnTM is subject to risks associated with fluctuations, particularly a decline, in the performance of the index caused by unpredictable volatility and movement in the prices of the index components. Trading in futures contracts on carbon emissions commodities, including trading in the index components, is speculative and can be extremely volatile. The commodity futures markets are subject to temporary distortions or other disruptions due to various factors, including the lack of liquidity in the markets, the participation of speculators and government regulation and intervention. Market prices of the index components may fluctuate rapidly based on numerous factors including but not limited to changes in supply and demand, domestic and foreign political or government actions and technological developments. These factors could adversely affect the value of the Index and, therefore, the value of your Securities. Cap & Trade mechanisms have arisen primarily due to relative international consensus on the correlation between the rise in Green House Gas emissions and the onset of Global Warming. Accordingly, changes in regulation and enforcement of Cap & Trade mechanisms as a result of changes in international consensus can adversely affect market behavior and the value of the Securities. “Barclays Capital Global Carbon IndexTM” and “Barclays Capital Global Carbon Index Total ReturnTM” are trademarks of Barclays Bank PLC and have been licensed for use by Barclays Capital in connection with the calculation of the Index. © 2008 BGINA. All rights reserved. iPath, iPath ETNs and the iPath logo are registered trademarks of Barclays Bank PLC. All other trademarks, servicemarks or registered trademarks are the property, and used with the permission, of their respective owners. 7034-iP-0608 BCY-M-040-06008 BARCLAYS CAPITAL