Please answer the given financial question based on the context.
Context: entergy arkansas , inc . management's financial discussion and analysis results of operations net income 2008 compared to 2007 net income decreased $ 92.0 million primarily due to higher other operation and maintenance expenses , higher depreciation and amortization expenses , and a higher effective income tax rate , partially offset by higher net revenue . the higher other operation and maintenance expenses resulted primarily from the write-off of approximately $ 70.8 million of costs as a result of the december 2008 arkansas court of appeals decision in entergy arkansas' base rate case . the base rate case is discussed in more detail in note 2 to the financial statements . 2007 compared to 2006 net income decreased $ 34.0 million primarily due to higher other operation and maintenance expenses , higher depreciation and amortization expenses , and a higher effective income tax rate . the decrease was partially offset by higher net revenue . net revenue 2008 compared to 2007 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 credits . following is an analysis of the change in net revenue comparing 2008 to 2007 . amount ( in millions ) .
||amount ( in millions )|
|2007 net revenue|$ 1110.6|
|rider revenue|13.6|
|purchased power capacity|4.8|
|volume/weather|-14.6 ( 14.6 )|
|other|3.5|
|2008 net revenue|$ 1117.9|
the rider revenue variance is primarily due to an energy efficiency rider which became effective in november 2007 . the establishment of the rider results in an increase in rider revenue and a corresponding increase in other operation and maintenance expense with no effect on net income . also contributing to the variance was an increase in franchise tax rider revenue as a result of higher retail revenues . the corresponding increase is in taxes other than income taxes , resulting in no effect on net income . the purchased power capacity variance is primarily due to lower reserve equalization expenses . the volume/weather variance is primarily due to the effect of less favorable weather on residential and commercial sales during the billed and unbilled sales periods compared to 2007 and a 2.9% ( 2.9 % ) volume decrease in industrial sales , primarily in the wood industry and the small customer class . billed electricity usage decreased 333 gwh in all sectors . see "critical accounting estimates" below and note 1 to the financial statements for further discussion of the accounting for unbilled revenues. .
Question: what percent of the net change in revenue between 2007 and 2008 was due to rider revenue?


Answer: The answer is:-1.86301