entergy louisiana , llc management's financial discussion and analysis 2007 compared to 2006 net revenue consists of operating revenues net of : 1 ) fuel , fuel-related expenses , and gas purchased for resale , 2 ) purchased power expenses , and 3 ) other regulatory charges ( credits ) . following is an analysis of the change in net revenue comparing 2007 to 2006 . amount ( in millions ) .
the base revenues variance is primarily due to increases effective september 2006 for the 2005 formula rate plan filing to recover lpsc-approved incremental deferred and ongoing capacity costs . see "state and local rate regulation" below and note 2 to the financial statements for a discussion of the formula rate plan filing . the volume/weather variance is due to increased electricity usage , including electricity sales during the unbilled service period . billed retail electricity usage increased a total of 666 gwh in all sectors compared to 2006 . see "critical accounting estimates" below and note 1 to the financial statements for further discussion of the accounting for unbilled revenues . the transmission revenue variance is primarily due to higher rates . the purchased power capacity variance is primarily due to higher purchased power capacity charges and the amortization of capacity charges effective september 2006 as a result of the formula rate plan filing in may 2006 . a portion of the purchased power capacity costs is offset in base revenues due to a base rate increase implemented to recover incremental deferred and ongoing purchased power capacity charges , as mentioned above . see "state and local rate regulation" below and note 2 to the financial statements for a discussion of the formula rate plan filing . gross operating revenues , fuel , purchased power expenses , and other regulatory charges ( credits ) gross operating revenues increased primarily due to : an increase of $ 143.1 million in fuel cost recovery revenues due to higher fuel rates and usage ; an increase of $ 78.4 million in base revenues , as discussed above ; and an increase of $ 37.5 million related to volume/weather , as discussed above . fuel and purchased power expenses increased primarily due to an increase in net area demand and an increase in deferred fuel expense as a result of higher fuel rates , as discussed above . other regulatory credits decreased primarily due to the deferral of capacity charges in 2006 in addition to the amortization of these capacity charges in 2007 as a result of the may 2006 formula rate plan filing ( for the 2005 test year ) with the lpsc to recover such costs through base rates effective september 2006 . see note 2 to the financial statements for a discussion of the formula rate plan and storm cost recovery filings with the lpsc. .
Amount (In Millions)
2006 net revenue $942.1
Base revenues 78.4
Volume/weather 37.5
Transmission revenue 9.2
Purchased power capacity (80.0)
Other 3.9
2007 net revenue $991.1
amount ( in millions )
2006 net revenue $ 942.1
base revenues 78.4
volume/weather 37.5
transmission revenue 9.2
purchased power capacity -80.0 ( 80.0 )
other 3.9
2007 net revenue $ 991.1
what percent of the net change in revenue between 2007 and 2008 was due to volume/weather?