devon energy corporation and subsidiaries notes to consolidated financial statements 2014 ( continued ) proved undeveloped reserves the following table presents the changes in our total proved undeveloped reserves during 2011 ( in mmboe ) . .
what was the percent of the proved undeveloped reserves in u.s . onshore as of december 31 2010 in north america
at december 31 , 2011 , devon had 782 mmboe of proved undeveloped reserves . this represents a 6% ( 6 % ) decrease as compared to 2010 and represents 26% ( 26 % ) of its total proved reserves . drilling activities increased devon 2019s proved undeveloped reserves 148 mmboe and resulted in the conversion of 130 mmboe , or 16% ( 16 % ) , of the 2010 proved undeveloped reserves to proved developed reserves . additionally , revisions other than price decreased devon 2019s proved undeveloped reserves 51 mmboe primarily due to its evaluation of certain u.s . onshore dry-gas areas , which it does not expect to develop in the next five years . the largest revisions relate to the dry-gas areas at carthage in east texas and the barnett shale in north texas . a significant amount of devon 2019s proved undeveloped reserves at the end of 2011 largely related to its jackfish operations . at december 31 , 2011 and 2010 , devon 2019s jackfish proved undeveloped reserves were 367 mmboe and 396 mmboe , respectively . development schedules for the jackfish reserves are primarily controlled by the need to keep the processing plants at their 35000 barrel daily facility capacity . processing plant capacity is controlled by factors such as total steam processing capacity , steam-oil ratios and air quality discharge permits . as a result , these reserves are classified as proved undeveloped for more than five years . currently , the development schedule for these reserves extends though the year 2025 . price revisions 2011 2014reserves decreased 21 mmboe due to lower gas prices and higher oil prices . the higher oil prices increased devon 2019s canadian royalty burden , which reduced devon 2019s oil reserves . 2010 2014reserves increased 72 mmboe due to higher gas prices , partially offset by the effect of higher oil prices . the higher oil prices increased devon 2019s canadian royalty burden , which reduced devon 2019s oil reserves . of the 72 mmboe price revisions , 43 mmboe related to the barnett shale and 22 mmboe related to the rocky mountain area . 2009 2014reserves increased 177 mmboe due to higher oil prices , partially offset by lower gas prices . the increase in oil reserves primarily related to devon 2019s jackfish thermal heavy oil reserves in canada . at the end of 2008 , 331 mmboe of reserves related to jackfish were not considered proved . however , due to higher prices , these reserves were considered proved as of december 31 , 2009 . significantly lower gas prices caused devon 2019s reserves to decrease 116 mmboe , which primarily related to its u.s . reserves . revisions other than price total revisions other than price for 2011 primarily related to devon 2019s evaluation of certain dry gas regions noted in the proved undeveloped reserves discussion above . total revisions other than price for 2010 and 2009 primarily related to devon 2019s drilling and development in the barnett shale. .