EX-99.2 BYLAWS 9 ex99-2.htm Prepared by Imprima

Exhibit 99.2

DEGOLYER AND MACNAUGHTON
5001 SPRING VALLEY ROAD
SUITE 800 EAST
DALLAS, TEXAS 75244

This is a digital representation of a DeGolyer and MacNaughton report.

Each file contained herein is intended to be a manifestation of certain data in the subject report and as such is subject to the definitions, qualifications, explanations, conclusions, and other conditions thereof. The information and data contained in each file may be subject to misinterpretation; therefore, the signed and bound copy of this report should be considered the only authoritative source of such information.

 


DEGOLYER AND MACNAUGHTON
5001 SPRING VALLEY ROAD
SUITE 800 EAST
DALLAS, TEXAS 75244


February 17,2012

YPF S. A.
Macacha Güemes 515
Ciudad Autonóma de Buenos Aires
Argentina

Gentlemen:

Pursuant to your request, we have conducted a reserves audit of the net proved crude oil, condensate, natural gas liquids (NGL), gasoline, and natural gas reserves, as of September 30, 2011, of certain properties owned by YPF S. A. (YPF) located in Argentina. This evaluation was completed on February 17, 2012. Reserves for these properties are termed Package 4. YPF has represented that these properties account for 20.4 percent on a net equivalent barrel basis of YPF’s net proved reserves as of September 30, 2011, that the proved undeveloped reserves estimated in this report constitute approximately 10.7 percent of all YPF’s proved undeveloped reserves, and that the net proved reserves estimates have been prepared in accordance with the reserves definitions of Rules 4-10(a) (1)-(32) of Regulation S-X of the Securities and Exchange Commission (SEC) of the United States. We have reviewed information provided to us by YPF that it represents to be YPF’s estimates of the net reserves, as of September 30, 2011, for the same properties as those which we evaluated. This report was prepared in accordance with guidelines specified in Item 1202 (a)(8) of Regulation S-K and is to be used for inclusion in certain SEC filings by YPF.

Reserves included herein are expressed as net reserves as represented by YPF. Gross reserves are defined as the total estimated petroleum to be produced from these properties after September 30, 2011. Net reserves are defined as that portion of the gross reserves attributable to the interests owned by YPF after deducting all interests owned by others.

Estimates of oil, condensate, NGL, gasoline, and natural gas should be regarded only as estimates that may change as further production history and



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DEGOLYER AND MACNAUGHTON

additional information become available. Not only are such reserves estimates based on that information which is currently available, but such estimates are also subject to the uncertainties inherent in the application of judgmental factors in interpreting such information.

Data used in this audit were obtained from reviews with YPF personnel, YPF files, from records on file with the appropriate regulatory agencies, and from public sources. In the preparation of this report we have relied, without independent verification, upon such information furnished by YPF with respect to property interests, production from such properties, current costs of operation and development, current prices for production, agreements relating to current and future operations and sale of production, and various other information and data that were accepted as represented. A field examination of the properties was not considered necessary for the purposes of this report.

Methodology and Procedures

Estimates of reserves were prepared by the use of appropriate geologic, petroleum engineering, and evaluation principles and techniques that are in accordance with practices recognized by the petroleum industry as presented in the publication of the Society of Petroleum Engineers entitled “Standards Pertaining to the Estimating and Auditing of Oil and Gas Reserves Information (Revision as of February 19, 2007).” The method or combination of methods used in the analysis of each reservoir was tempered by experience with similar reservoirs, stage of development, quality and completeness of basic data, and production history, and were methods that we considered to be appropriate and necessary to establish reserves quantities and reserves categorization that conform to SEC definitions and guidelines.

When applicable, the volumetric method was used to estimate the original oil in place (OOIP) and the original gas in place (OGIP). Structure and isopach maps were constructed to estimate reservoir volume. Electrical logs, radioactivity logs, core analyses, and other available data were used to prepare these maps as well as to estimate representative values for porosity and water saturation. When adequate data were available and when circumstances justified, material balance and other engineering methods were used to estimate OOIP or OGIP.



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DEGOLYER AND MACNAUGHTON

Estimates of ultimate recovery were obtained after applying recovery factors to OOIP or OGIP. These recovery factors were based on consideration of the type of energy inherent in the reservoirs, analyses of the petroleum, the structural positions of the properties, and the production histories. When applicable, material balance and other engineering methods were used to estimate recovery factors. An analysis of reservoir performance, including production rate, reservoir pressure, and gas-oil ratio behavior, was used in the estimation of reserves.

For depletion-type reservoirs or those whose performance disclosed a reliable decline in producing-rate trends or other diagnostic characteristics, reserves were estimated by the application of appropriate decline curves or other performance relationships. In the analyses of production-decline curves, reserves were estimated only to the limits of economic production or to the limit of the production licenses as appropriate.

Proved developed reserves estimated herein were estimated using decline-curve analysis. Proved undeveloped reserves were estimated for direct offset well locations that YPF has represented will be drilled within five years.

Definition of Reserves

Petroleum reserves estimated by YPF and by us included in this report are classified as proved. Only proved reserves have been evaluated for this report. Reserves classifications used by YPF and by us in this report are in accordance with the reserves definitions of Rules 4-lO(a) (1)-(32) of Regulation S-X of the SEC. Reserves are judged to be economically producible in future years from known reservoirs under existing economic and operating conditions and assuming continuation of current regulatory practices using conventional production methods and equipment. In the analyses of production-decline curves, reserves were estimated only to the limit of economic rates of production under existing economic and operating conditions using prices and costs consistent with the effective date of this report, including consideration of changes in existing prices provided only by contractual arrangements but not including escalations based upon future conditions. The petroleum reserves are classified as follows:

Proved oil and gas reserves – Proved oil and gas reserves are those quantities of oil and gas, which, by analysis of geoscience and engineering data, can be estimated with reasonable certainty to be



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DEGOLYER AND MACNAUGHTON

economically producible–from a given date forward, from known reservoirs, and under existing economic conditions, operating methods, and government regulations–prior to the time at which contracts providing the right to operate expire, unless evidence indicates that renewal is reasonably certain, regardless of whether deterministic or probabilistic methods are used for the estimation. The project to extract the hydrocarbons must have commenced or the operator must be reasonably certain that it will commence the project within a reasonable time.

  (i) The area of the reservoir considered as proved includes:

  (A) The area identified by drilling and limited by fluid contacts, if any, and (B) Adjacent undrilled portions of the reservoir that can, with reasonable certainty, be judged to be continuous with it and to contain economically producible oil or gas on the basis of available geoscience and engineering data.

  (ii) In the absence of data on fluid contacts, proved quantities in a reservoir are limited by the lowest known hydrocarbons (LKH) as seen in a well penetration unless geoscience, engineering, or performance data and reliable technology establishes a lower contact with reasonable certainty.

  (iii) Where direct observation from well penetrations has defined a highest known oil (HKO) elevation and the potential exists for an associated gas cap, proved oil reserves may be assigned in the structurally higher portions of the reservoir only if geoscience, engineering, or performance data and reliable technology establish the higher contact with reasonable certainty.

  (iv) Reserves which can be produced economically through application of improved recovery techniques (including, but not limited to, fluid injection) are included in the proved classification when:

  (A) Successful testing by a pilot project in an area of the reservoir with properties no more favorable than in the reservoir as a whole, the operation of an installed program in the reservoir or an analogous reservoir, or other evidence using



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  reliable technology establishes the reasonable certainty of the engineering analysis on which the project or program was based; and (B) The project has been approved for development by all necessary parties and entities, including governmental entities.

  (v) Existing economic conditions include prices and costs at which economic producibility from a reservoir is to be determined. The price shall be the average price during the 12-month period prior to the ending date of the period covered by the report, determined as an unweighted arithmetic average of the first-day-of-the-month price for each month within such period, unless prices are defined by contractual arrangements, excluding escalations based upon future conditions.

Developed oil and gas reserves – Developed oil and gas reserves are reserves of any category that can be expected to be recovered:

  (i) Through existing wells with existing equipment and operating methods or in which the cost of the required equipment is relatively minor compared to the cost of a new well; and

  (ii) Through installed extraction equipment and infrastructure operational at the time of the reserves estimate if the extraction is by means not involving a well.

Undeveloped oil and gas reserves – Undeveloped oil and gas reserves are reserves of any category that are expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion.

  (i) Reserves on undrilled acreage shall be limited to those directly offsetting development spacing areas that are reasonably certain of production when drilled, unless evidence using reliable technology exists that establishes reasonable certainty of economic producibility at greater distances.



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  (ii) Undrilled locations can be classified as having undeveloped reserves only if a development plan has been adopted indicating that they are scheduled to be drilled within five years, unless the specific circumstances justify a longer time.

  (iii) Under no circumstances shall estimates for undeveloped reserves be attributable to any acreage for which an application of fluid injection or other improved recovery technique is contemplated, unless such techniques have been proved effective by actual projects in the same reservoir or an analogous reservoir, as defined in [section 210.4-10 (a) Definitions], or by other evidence using reliable technology establishing reasonable certainty.

Economic Basis for Reserves Estimates

Future prices and costs were estimated using initial prices and costs provided byYPF S.A. as of September 30,2011.

Future prices were estimated using guidelines established by the SEC and the Financial Accounting Standards Board. Proved reserves were based on projections of estimated future production and revenue prepared for these properties.

     The assumption used for estimating future prices and costs are as follows:

  Liquids Prices

  Based on information provided by YPF S.A., the government-regulated price of oil, condensate, and gasoline was U.S.$61.40 per barrel for the Neuquina Basin, $56.40 for the Cuyana Basin, and U.S.$57.30 per barrel for the San Jorge Basin. According to information provided by YPF S.A., the government-regulated oil prices will expire at year-end 2016. YPF S.A. has represented that, after such time, the oil, condensate, and gasoline prices provided by YPF S.A. will be based on a 12-month average West Texas Intermediate price, calculated as the unweighted arithmetic average of the



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DEGOLYER AND MACNAUGHTON

  first-day-of-the-month price for each month within the 12-month period prior to the end of the reporting period. YPF S.A. supplied differentials by field to a West Texas Intermediate reference price of U.S.$94.31 per barrel and the prices were held constant thereafter. The volume-weighted average price attributable to estimated proved reserves was $71.51 per barrel.

  YPF S.A. has represented that initial NGL prices were U.S.$26.47 per barrel for the Neuquina Basin and U.S.$27.12 per barrel for the Cuyana Basin and were to be held constant for the life of the properties. YPF S.A. has represented that these prices were calculated as the unweighted arithmetic average of the first-day-of-the-month price for each month within the 12-month period prior to the end of the reporting period. The volume-weighted average price attributable to estimated proved reserves was $26.51 per barrel.

  Natural Gas Prices

  YPF S.A. has represented that the natural gas prices were U.S.$1.99 per million British thermal units (MMBtu) for San Jorge Basin and U.S.$2.21 per MMBtu for Neuquina and Cuyana Basins and were held constant thereafter. YPF S.A. has represented that these prices were calculated as the unweighted arithmetic average of the first-day-of-the-month price for each month within the 12-month period prior to the end of the reporting period. The volume-weighted average price attributable to estimated proved reserves was $2.19 per MMBtu.

  Operating Expenses and Capital Costs

  Operating expenses and capital costs, based on information provided by YPF S.A., were used in estimating future costs required to operate the properties. In certain cases, future costs, either higher or lower than existing costs, may have been used because of anticipated changes in operating conditions. These costs were not escalated for inflation.



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While the oil and gas industry may be subject to regulatory changes from time to time that could affect an industry participant’s ability to recover its oil and gas reserves, we are not aware of any such governmental actions which would restrict the recovery of the September 30, 2011, estimated oil and gas volumes. The reserves estimated in this report can be produced under current regulatory guidelines.

YPF has represented that estimated net proved reserves attributable to the reviewed properties are based on the definitions of proved reserves of the SEC. YPF represents that its estimates of the net proved reserves attributable to these properties which represent 20.4 percent of YPF’s reserves on a net equivalent basis are as follows, expressed in thousands of barrels (Mbbl), millions of cubic feet (MMcf), and thousands of barrels of oil equivalent (Mboe):

Estimated by YPF
Net Proved Reserves
as of September 30, 2011

Oil and Condensate
(Mbbl)
NGL
(Mbbl)
Gasoline
(Mbbl)
Marketable Gas
(MMcf)
Oil Equivalent (Mboe )





Proved Developed
  Chihuido La Salina Sur Area 2,647 2,364 663 38,627 12,111
  Chihuido La Salina Area 13,017 5,332 1,245 76,898 32,411
  El Portón (Mz) Area 833 915 140 13,178 4,084
  El Portón (Nq) Area 3,023 5,922 963 86,969 24,403
  Cañadón Yatel Area 3,702 0 0 10,027 5,373
  Las Heras Area 3,530 0 0 2,990 4,028
  Guanaco Blanco Area 71 0 0 0 71
  La Ventana “Grupo A” Area 448 0 0 80 462
  La Ventana Central Area 18,227 705 0 2,717 19,385
  La Ventana Area 1,843 0 0 326 1,897
  La Ventana Cañada Dura Area 0 0 0 0 0
  Vizcacheras Cañada Dura Area 3,748 0 0 249 3,790
  Vizcacheras Area 21,409 414 0 3,082 22,337
  Desfiladero Bayo (Mz) Area 10,824 0 0 846 10,965
  Desfiladero Bayo (Nq) Area 3,023 0 0 192 3,055
  Chihuido Sierra Negra Area 29,918 0 0 7,631 31,189
  Señal Picada (Nq) Area 201 0 0 25 205
  Señal Picada (RN) Area 8,191 0 0 1,256 8,401





Total Proved Developed 124,655 15,653 3,011 245,093 184,167
Proved Undeveloped
  Chihuido La Salina Sur Area 11 381 50 3,913 1,095
  Chihuido La Salina Area 453 649 92 7,163 2,388
  El Portón (Mz) Area 148 119 31 2,390 697
  El Portón (Nq) Area 519 738 177 13,912 3,753
  Cañadón Yatel Area 1,573 0 0 17,043 4,414
  Las Heras Area 1,628 0 0 1,585 1,892
  Guanaco Blanco Area 0 0 0 0 0
  La Ventana “Grupo A” Area 0 0 0 0 0



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DEGOLYER AND MACNAUGHTON

Estimated by YPF – (Continued)

Oil and Condensate
(Mbbl)
NGL
(Mbbl)
Gasoline
(Mbbl)
Marketable Gas
(MMcf)
Oil Equivalent (Mboe )





Proved Developed(Continued)
  La Ventana Central Area 831 27 0 122 878
  La Ventana Area 0 0 0 0 0
  La Ventana Cañada Dura Area 0 0 0 0 0
  Vizcacheras Cañada Dura Area 0 0 0 0 0
  Vizcacheras Area 1,282 0 0 185 1,313
  Desfiladero Bayo (Mz) Area 3,397 0 0 428 3,468
  Desfiladero Bayo (Nq) Area 1,482 0 0 102 1,499
  Chihuido Sierra Negra Area 179 0 0 1,609 447
  Señal Picada (Nq) Area 0 0 0 0 0
  Señal Picada (RN) Area 1,517 0 0 234 1,556





Total Proved Undeveloped 13,020 1,915 350 48,686 23,400
Total Proved
  Chihuido La Salina Sur Area 2,658 2,745 713 42,540 13,206
  Chihuido La Salina Area 13,470 5,982 1,337 84,061 34,799
  El Portón (Mz) Area 981 1,034 171 15,568 4,781
  El Portón (Nq) Area 3,542 6,660 1,141 100,881 28,156
  Cañadón Yatel Area 5,275 0 0 27,070 9,787
  Las Heras Area 5,158 0 0 4,575 5,920
  Guanaco Blanco Area 71 0 0 0 71
  La Ventana “Grupo A” Area 448 0 0 80 462
  La Ventana Central Area 19,058 733 0 2,840 20,263
  La Ventana Area 1,843 0 0 326 1,897
  La Ventana Cañada Dura Area 0 0 0 0 0
  Vizcacheras Cañada Dura Area 3,748 0 0 249 3,790
  Vizcacheras Area 22,691 414 0 3,267 23,650
  Desfiladero Bayo (Mz) Area 14,221 0 0 1,274 14,433
  Desfiladero Bayo (Nq) Area 4,505 0 0 294 4,554
  Chihuido Sierra Negra Area 30,097 0 0 9,240 31,636
  Señal Picada (Nq) Area 201 0 0 25 205
  Señal Picada (RN) Area 9,708 0 0 1,491 9,957





Total Proved 137,675 17,568 3,361 293,779 207,567

Note: Gas is converted to oil equivalent using a factor of6,000 cubic feet of gas per 1 barrel of oil equivalent.

Our estimates of YPF’s net proved reserves attributable to the reviewed properties are based on the definitions of proved reserves of the SEC and are as follows, expressed in thousands of barrels (Mbbl), millions of cubic feet (MMcf), and thousands of barrels of oil equivalent (Mboe):



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DEGOLYER AND MACNAUGHTON

Estimated by DeGolyer and MacNaughton
Net Proved Reserves
as of September 30, 2011

Oil and Condensate
(Mbbl)
NGL
(Mbbl)
Gasoline
(Mbbl)
Marketable Gas
(MMcf)
Oil Equivalent (Mboe )





Proved Developed
  Chihuido La Salina Sur Area 2,589 2,362 664 38,615 12,051
  Chihuido La Salina Area 13,020 5,329 1,245 76,895 32,410
  El Portón (Mz) Area 834 913 142 13,173 4,085
  El Portón (Nq) Area 3,021 5,924 964 86,974 24,405
  Cañadón Yatel Area 3,701 0 0 10,029 5,373
  Las Heras Area 3,530 0 0 2,992 4,029
  Guanaco Blanco Area 72 0 0 0 72
  La Ventana “Grupo A” Area 449 0 0 86 463
  La Ventana Central Area 18,226 705 0 2,716 19,384
  La Ventana Area 1,842 0 0 325 1,896
  La Ventana Cañada Dura Area 0 0 0 0 0
  Vizcacheras Cañada Dura Area 3,750 0 0 249 3,792
  Vizcacheras Area 21,412 414 0 3,086 22,340
  Desfiladero Bayo (Mz) Area 10,739 0 0 841 10,879
  Desfiladero Bayo (Nq) Area 3,022 0 0 190 3,054
  Chihuido Sierra Negra Area 29,801 0 0 7,499 31,051
  Señal Picada (Nq) Area 112 0 0 24 116
  Señal Picada (RN) Area 8,193 0 0 1,253 8,402





Total Proved Developed 124,313 15,647 3,015 244,947 183,802
Proved Undeveloped
  Chihuido La Salina Sur Area 13 383 48 3,911 1,096
  Chihuido La Salina Area 449 652 90 7,165 2,385
  El Portón (Mz) Area 147 121 30 2,397 698
  El Portón (Nq) Area 520 738 176 13,907 3,752
  Cañadón Yatel Area 1,576 0 0 17,036 4,415
  Las Heras Area 1,629 0 0 1,588 1,894
  Guanaco Blanco Area 0 0 0 0 0
  La Ventana “Grupo A” Area 0 0 0 0 0
  La Ventana Central Area 831 27 0 124 879
  La Ventana Area 0 0 0 0 0
  La Ventana Cañada Dura Area 0 0 0 0 0
  Vizcacheras Cañada Dura Area 0 0 0 0 0
  Vizcacheras Area 1,281 0 0 187 1,312
  Desfiladero Bayo (Mz) Area 3,335 0 0 423 3,406
  Desfiladero Bayo (Nq) Area 1,482 0 0 101 1,499
  Chihuido Sierra Negra Area 1,639 0 0 1,831 1,944
  Señal Picada (Nq) Area 0 0 0 0 0
  Señal Picada (RN) Area 1,362 0 0 215 1,398





Total Proved Undeveloped 14,264 1,921 344 48,885 24,678
Total Proved
  Chihuido La Salina Sur Area 2,602 2,745 712 42,526 13,147
  Chihuido La Salina Area 13,469 5,981 1,335 84,060 34,795
  El Portón (Mz) Area 981 1,034 172 15,570 4,783
  El Portón (Nq) Area 3,541 6,662 1,140 100,881 28,157
  Cañadón Yatel Area 5,277 0 0 27,065 9,788
  Las Heras Area 5,159 0 0 4,580 5,923
  Guanaco Blanco Area 72 0 0 0 72
  La Ventana “Grupo A” Area 449 0 0 86 463



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DEGOLYER AND MACNAUGHTON

Estimated by DeGolyer and MacNaughton – (Continued)

Oil and Condensate
(Mbbl)
NGL
(Mbbl)
Gasoline
(Mbbl)
Marketable Gas
(MMcf)
Oil Equivalent (Mboe )





Total(Continued)
  La Ventana Central Area 19,057 732 0 2,840 20,263
  La Ventana Area 1,842 0 0 325 1,896
  La Ventana Cañada Dura Area 0 0 0 0 0
  Vizcacheras Cañada Dura Area 3,750 0 0 249 3,792
  Vizcacheras Area 22,693 414 0 3,273 23,652
  Desfiladero Bayo (Mz) Area 14,074 0 0 1,264 14,285
  Desfiladero Bayo (Nq) Area 4,504 0 0 291 4,553
  Chihuido Sierra Negra Area 31,440 0 0 9,330 32,995
  Señal Picada (Nq) Area 112 0 0 24 116
  Señal Picada (RN) Area 9,555 0 0 1,468 9,800





Total Proved 138,577 17,568 3,359 293,832 208,480

Note: Gas is converted to oil equivalent using a factor of 6,000 cubic feet of gas per 1 barrel of oil equivalent.

In our opinion, the information relating to estimated proved reserves of oil, condensate, natural gas liquids, and gas contained in this report has been prepared in accordance with Paragraphs 932-235-50-4, 932-235-50-6, 932-235-50-7, and 932-235-50-9 of the Accounting Standards Update 932-235-50, Extractive Industries – Oil and Gas (Topic 932): Oil and Gas Reserve Estimation and Disclosures (January 2010) of the Financial Accounting Standards Board and Rules 4-10(a) (1)-(32) of Regulation S-X and Rules 302(b), 1201, 1202(a) (1), (2), (3), (4), (8), and 1203(a) of Regulation S-K of the Securities and Exchange Commission; provided, however, that estimates of proved developed and proved undeveloped reserves are not presented at the beginning of the year.

To the extent the above-enumerated rules, regulations, and statements require determinations of an accounting or legal nature, we, as engineers, are necessarily unable to express an opinion as to whether the above-described information is in accordance therewith or sufficient therefor.

In comparing the detailed net proved reserves estimates prepared by us and by YPF, we have found differences, both positive and negative, resulting in an aggregate difference of 0.4 percent when compared on the basis of net equivalent barrels. It is our opinion that the net proved reserves estimates prepared by YPF on the properties reviewed by us and referred to above, when compared on the basis of net equivalent barrels, in aggregate, do not differ materially from those prepared by us.



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DeGolyer and MacNaughton is an independent petroleum engineering consulting firm that has been providing petroleum consulting services throughout the world since 1936. DeGolyer and MacNaughton does not have any financial interest, including stock ownership, in YPF. Our fees were not contingent on the results of our evaluation. This letter report has been prepared at the request ofYPF. DeGolyer and MacNaughton has used all assumptions, data, procedures, and methods that it considers necessary and appropriate to prepare this report.

 

Submitted,

/s/ DeGOLYER and MacNAUGHTON
DeGOLYER and MacNAUGHTON
Texas Registered Engineering Firm F-716





 
/s/ Thomas C. Pence, P.E.
Thomas C. Pence, P.E.
Senior Vice President
DeGolyer and MacNaughton

 

 


DEGOLYER AND MACNAUGHTON

CERTIFICATE of QUALIFICATION

I, Thomas C. Pence, Petroleum Engineer with DeGolyer and MacNaughton, 5001 Spring Valley Road, Suite 800 East, Dallas, Texas, 75244 U.S.A., hereby certify:

1. That I am a Senior Vice President with DeGolyer and MacNaughton, which company did prepare the letter report addressed to YPF dated February 17, 2012, and that I, as Senior Vice President, was responsible for the preparation of this report.

2. That I attended Texas A&M University, and that I graduated with a degree in Petroleum Engineering in the year 1982; that I am a Registered Professional Engineer in the State of Texas; that I am a member of the International Society of Petroleum Engineers; and that I have in excess of 29 years of experience in the oil and gas reservoir studies and reserves evaluations.

/s/ Thomas C. Pence, P.E.
Thomas C. Pence, P.E.
Senior Vice President
DeGolyer and MacNaughton