Please answer the given financial question based on the context.
Context: entergy new orleans , inc . and subsidiaries management 2019s financial discussion and analysis results of operations net income 2016 compared to 2015 net income increased $ 3.9 million primarily due to higher net revenue , partially offset by higher depreciation and amortization expenses , higher interest expense , and lower other income . 2015 compared to 2014 net income increased $ 13.9 million primarily due to lower other operation and maintenance expenses and higher net revenue , partially offset by a higher effective income tax rate . net revenue 2016 compared to 2015 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 . following is an analysis of the change in net revenue comparing 2016 to 2015 . amount ( in millions ) .
||amount ( in millions )|
|2015 net revenue|$ 293.9|
|retail electric price|39.0|
|net gas revenue|-2.5 ( 2.5 )|
|volume/weather|-5.1 ( 5.1 )|
|other|-8.1 ( 8.1 )|
|2016 net revenue|$ 317.2|
the retail electric price variance is primarily due to an increase in the purchased power and capacity acquisition cost recovery rider , as approved by the city council , effective with the first billing cycle of march 2016 , primarily related to the purchase of power block 1 of the union power station . see note 14 to the financial statements for discussion of the union power station purchase . the net gas revenue variance is primarily due to the effect of less favorable weather on residential and commercial sales . the volume/weather variance is primarily due to a decrease of 112 gwh , or 2% ( 2 % ) , in billed electricity usage , partially offset by the effect of favorable weather on commercial sales and a 2% ( 2 % ) increase in the average number of electric customers. .
Question: what was the combined impact in millions on 2016 net revenue from the net gas revenue adjustment , the volume/weather adjustment , and other adjustments?
Answer:
-15.7