item 7 . management 2019s discussion and analysis of financial condition and results of operations results of operations 2013 highmount 2013 ( continued ) highmount 2019s revenues , profitability and future growth depend substantially on natural gas and ngl prices and highmount 2019s ability to increase its natural gas and ngl production . in recent years , there has been significant price volatility in natural gas and ngl prices due to a variety of factors highmount cannot control or predict . these factors , which include weather conditions , political and economic events , and competition from other energy sources , impact supply and demand for natural gas , which determines the pricing . in recent months , natural gas prices decreased significantly due largely to increased onshore natural gas production , plentiful levels of working gas in storage and reduced commercial demand . the increase in the onshore natural gas production was due largely to increased production from 201cunconventional 201d sources of natural gas such as shale gas , coalbed methane , tight sandstones and methane hydrates , made possible in recent years by modern technology in creating extensive artificial fractures around well bores and advances in horizontal drilling technology . other key factors contributing to the softness of natural gas prices likely included a lower level of industrial demand for natural gas , as a result of the ongoing economic downturn , and relatively low crude oil prices . due to industry conditions , in february of 2009 highmount elected to terminate contracts for five drilling rigs at its permian basin property in the sonora , texas area . the estimated fee payable to the rig contractor for exercising this early termination right will be approximately $ 23 million . in light of these developments , highmount will reduce 2009 production volumes through decreased drilling activity . in addition , the price highmount realizes for its gas production is affected by highmount 2019s hedging activities as well as locational differences in market prices . highmount 2019s decision to increase its natural gas production is dependent upon highmount 2019s ability to realize attractive returns on its capital investment program . returns are affected by commodity prices , capital and operating costs . highmount 2019s operating income , which represents revenues less operating expenses , is primarily affected by revenue factors , but is also a function of varying levels of production expenses , production and ad valorem taxes , as well as depreciation , depletion and amortization ( 201cdd&a 201d ) expenses . highmount 2019s production expenses represent all costs incurred to operate and maintain wells and related equipment and facilities . the principal components of highmount 2019s production expenses are , among other things , direct and indirect costs of labor and benefits , repairs and maintenance , materials , supplies and fuel . in general , during 2008 highmount 2019s labor costs increased primarily due to higher salary levels and continued upward pressure on salaries and wages as a result of the increased competition for skilled workers . in response to these market conditions , in 2008 highmount implemented retention programs , including increases in compensation . production expenses during 2008 were also affected by increases in the cost of fuel , materials and supplies . the higher cost environment discussed above continued during all of 2008 . during the fourth quarter of 2008 the price of natural gas declined significantly while operating expenses remained high . this environment of low commodity prices and high operating expenses continued until december of 2008 when highmount began to see evidence of decreasing operating expenses and drilling costs . highmount 2019s production and ad valorem taxes increase primarily when prices of natural gas and ngls increase , but they are also affected by changes in production , as well as appreciated property values . highmount calculates depletion using the units-of-production method , which depletes the capitalized costs and future development costs associated with evaluated properties based on the ratio of production volumes for the current period to total remaining reserve volumes for the evaluated properties . highmount 2019s depletion expense is affected by its capital spending program and projected future development costs , as well as reserve changes resulting from drilling programs , well performance , and revisions due to changing commodity prices . presented below are production and sales statistics related to highmount 2019s operations: .
what is the 2008 rate of increase in oil production/sales?
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