Note 5. Capitalized Exploratory Well Costs

We capitalize exploratory well costs until a determination is made that the well has found proved reserves or is deemed noncommercial. If a well is deemed to be noncommercial, the well costs are immediately charged to exploration expense as dry hole cost.

Changes in capitalized exploratory well costs are as follows and exclude amounts that were capitalized and subsequently expensed in the same period:



	Year Ended December 31,
(millions)	2014			2013			2012
Capitalized Exploratory Well Costs, Beginning of Period	$	1,301		$	900		$	696
Additions to Capitalized Exploratory Well Costs Pending Determination of Proved Reserves	316			581			360
Reclassified to Proved Oil and Gas Properties Based on Determination of Proved Reserves or to Assets Held for Sale⁽¹⁾	(196		)	(177		)	(18		)
Capitalized Exploratory Well Costs Charged to Expense ⁽²⁾	(84		)	(3		)	(114		)
Other ⁽³⁾	—			—			(24		)
Capitalized Exploratory Well Costs, End of Period	$	1,337		$	1,301		$	900


⁽¹⁾	The 2014 amount primarily relates to the Dantzler well (deepwater Gulf of Mexico), for which we sanctioned a development plan, and the Tanin and Karish wells (offshore Israel), which were reclassified to assets held for sale. The 2013 amount relates primarily to Gunflint (deepwater Gulf of Mexico), for which we sanctioned a development plan.


⁽²⁾	The 2014 amount relates to non-core onshore US exploratory well costs and the Scotia exploratory well (offshore Falkland Islands) which were determined to be non-commercial. The 2012 amount primarily represents deepwater Gulf of Mexico exploratory well costs.


⁽³⁾	The 2012 amount relates to North Sea exploratory well costs included in discontinued operations. See Note 3. Property Transactions.

The following table provides an aging of capitalized exploratory well costs based on the date that drilling commenced, and the number of projects that have been capitalized for a period greater than one year:



	December 31,
(millions)	2014		2013		2012
Exploratory Well Costs Capitalized for a Period of One Year or Less	$	247	$	568	$	355
Exploratory Well Costs Capitalized for a Period Greater Than One Year Since Commencement of Drilling	1,090		733		545
Balance at End of Period	$	1,337	$	1,301	$	900
Number of Projects with Exploratory Well Costs That Have Been Capitalized for a Period Greater Than One Year Since Commencement of Drilling	13		13		14

The following table provides a further aging of those exploratory well costs that have been capitalized for a period greater than one year since the commencement of drilling as of December 31, 2014:



		Suspended Since
Country/Project (millions)	Total	2012 - 2013	2010 - 2011	2009 & Prior	Progress
Onshore US
Northeast Nevada	23	23	—	—	Analyzing results from our first four exploratory vertical wells and evaluating potential for production tests
Deepwater Gulf of Mexico
Troubadour	47	47	—	—	Evaluating development scenarios for this 2013 natural gas discovery including subsea tieback to existing infrastructure
Offshore Equatorial Guinea
Diega (Block O) and Carmen (Block I)	216	111	52	53	Evaluating regional development scenarios for this 2008 crude oil discovery. We drilled subsequent appraisal wells. During 2014, conducted additional seismic activity over Blocks O and I and are engaged in processing the newly-acquired seismic data.
Carla (Block O)	149	137	12	—	Evaluating regional development scenarios for this 2011 crude oil discovery. We drilled subsequent appraisal wells. During 2014, we conducted additional seismic activity over Blocks O and I and are engaged in processing the newly-acquired seismic data.
Felicita (Block O)	39	4	6	29	Evaluating regional development plans for this 2008 condensate and natural gas discovery. A natural gas development team is working with the governments of Equatorial Guinea and Cameroon to evaluate natural gas monetization options and finalize a data exchange agreement between the two countries.
Yolanda (Block I)	20	3	3	14	Evaluating regional development plans for this 2007 condensate and natural gas discovery. A natural gas development team is working with the governments of Equatorial Guinea and Cameroon to evaluate natural gas monetization options. In addition, we are working to finalize a data exchange agreement between the two countries.
Offshore Cameroon
YoYo	47	4	9	34	Working with the government to assess commercialization of this 2007 condensate and natural gas discovery. A natural gas development team is working with the governments of Equatorial Guinea and Cameroon to evaluate natural gas monetization options and finalize a data exchange agreement between the two countries.
Offshore Israel ⁽¹⁾
Leviathan	181	71	110	—	During 2014, we received the Leviathan Development and Production Leases, submitted a development plan to the government and engaged in natural gas marketing activities. We are working to resolve antitrust and other regulatory matters with the Israeli government.
Leviathan-1 Deep	78	51	27	—	Well did not reach the target interval; developing future drilling plans to test this deep oil concept, which is held by the Leviathan Development and Production Leases. We are working on potential well design and placement.
Dalit	26	4	2	20	Submitted a development plan to the government to develop this 2009 natural gas discovery as a tie-in to existing infrastructure.
Dolphin 1	25	3	22	—	Reviewing regional development scenarios for this 2011 natural gas discovery, including a potential tieback to Leviathan. We have applied to the government for a commerciality ruling.
Offshore Cyprus



Cyprus	196		139		57		—		Discussing monetization options with the Cyprus government for this 2011 natural gas discovery. In May 2014, our application for renewal of the PSC for two additional years was approved. We plan to submit a plan of development to the government in 2015.
Other
Projects less than $20 million	43		33		4		6		Continuing to drill and evaluate wells
Total	$	1,090	$	630	$	304	$	156

⁽¹⁾

In March 2014, we and our partners reached an agreement with the Israel Antitrust Authority on various matters (Consent Decree). The Consent Decree, which was subject to final approval by the Antitrust Tribunal, granted the rights, to us and our partners, to jointly market natural gas from the Leviathan field. Also as a result of the Consent Decree, we agreed to divest our Tanin and Karish natural gas discoveries. However, on December 23, 2014, we and our partners in the Leviathan field were advised by the Israel Antitrust Authority of its decision to not submit the Consent Decree to the Antitrust Tribunal for final approval. This is a matter that we believed was resolved some time ago and we had received recent assurances from the Antitrust Authority that approval was forthcoming. We requested an oral hearing with the Antitrust Authority, which took place on January 27, 2015, and await final disposition.