Financial report context:
selling , general , and administrative expenses selling , general , and administrative expenses increased to $ 65.2 million in 2010 from $ 52.9 million in 2009 due primarily to increases in compensation expense and recruitment costs , principally in connection with higher headcount in 2010 , and an increase in non-cash compensation expense for the reasons described above . cost of goods sold cost of goods sold in 2010 and 2009 was $ 2.1 million and $ 1.7 million , respectively , and consisted primarily of royalties and other period costs related to arcalyst ae commercial supplies . to date , arcalyst ae shipments to our customers have primarily consisted of supplies of inventory manufactured and expensed as research and development costs prior to fda approval in 2008 ; therefore , the costs of these supplies were not included in costs of goods sold . other income and expense investment income decreased to $ 2.1 million in 2010 from $ 4.5 million in 2009 , due primarily to lower yields on , and lower average balances of , cash and marketable securities . interest expense increased to $ 9.1 million in 2010 from $ 2.3 million in 2009 . interest expense is primarily attributable to the imputed interest portion of payments to our landlord , commencing in the third quarter of 2009 , to lease newly constructed laboratory and office facilities in tarrytown , new york . income tax expense ( benefit ) in 2010 , we did not recognize any income tax expense or benefit . in 2009 , we recognized a $ 4.1 million income tax benefit , consisting primarily of ( i ) $ 2.7 million resulting from a provision in the worker , homeownership , and business assistance act of 2009 that allowed us to claim a refund of u.s . federal alternative minimum tax that we paid in 2008 , and ( ii ) $ 0.7 million resulting from a provision in the american recovery and reinvestment act of 2009 that allowed us to claim a refund for a portion of our unused pre-2006 research tax credits . years ended december 31 , 2009 and 2008 net loss regeneron reported a net loss of $ 67.8 million , or $ 0.85 per share ( basic and diluted ) , for the year ended december 31 , 2009 , compared to a net loss of $ 79.1 million , or $ 1.00 per share ( basic and diluted ) for 2008 . the decrease in our net loss in 2009 was principally due to higher collaboration revenue in connection with our antibody collaboration with sanofi-aventis , receipt of a $ 20.0 million substantive performance milestone payment in connection with our vegf trap-eye collaboration with bayer healthcare , and higher arcalyst ae sales , partly offset by higher research and development expenses , as detailed below . revenues revenues in 2009 and 2008 consist of the following: .

Financial table:
( in millions ): collaboration revenue
( in millions ): sanofi-aventis; 2009: $ 247.2; 2008: $ 154.0
( in millions ): bayer healthcare; 2009: 67.3; 2008: 31.2
( in millions ): total collaboration revenue; 2009: 314.5; 2008: 185.2
( in millions ): technology licensing revenue; 2009: 40.0; 2008: 40.0
( in millions ): net product sales; 2009: 18.4; 2008: 6.3
( in millions ): contract research and other revenue; 2009: 6.4; 2008: 7.0
( in millions ): total revenue; 2009: $ 379.3; 2008: $ 238.5

Additional report context:
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Question: what percentage of total revenue was bayer healthcare in 2009?
Answer: 18%