recognition of deferred revenue related to sanofi-aventis 2019 $ 85.0 million up-front payment decreased in 2010 compared to 2009 due to the november 2009 amendments to expand and extend the companies 2019 antibody collaboration . in connection with the november 2009 amendment of the discovery agreement , sanofi-aventis is funding up to $ 30 million of agreed-upon costs incurred by us to expand our manufacturing capacity at our rensselaer , new york facilities , of which $ 23.4 million was received or receivable from sanofi-aventis as of december 31 , 2010 . revenue related to these payments for such funding from sanofi-aventis is deferred and recognized as collaboration revenue prospectively over the related performance period in conjunction with the recognition of the original $ 85.0 million up-front payment . as of december 31 , 2010 , $ 79.8 million of the sanofi-aventis payments was deferred and will be recognized as revenue in future periods . in august 2008 , we entered into a separate velocigene ae agreement with sanofi-aventis . in 2010 and 2009 , we recognized $ 1.6 million and $ 2.7 million , respectively , in revenue related to this agreement . bayer healthcare collaboration revenue the collaboration revenue we earned from bayer healthcare , as detailed below , consisted of cost sharing of regeneron vegf trap-eye development expenses , substantive performance milestone payments , and recognition of revenue related to a non-refundable $ 75.0 million up-front payment received in october 2006 and a $ 20.0 million milestone payment received in august 2007 ( which , for the purpose of revenue recognition , was not considered substantive ) . years ended bayer healthcare collaboration revenue december 31 .

bayer healthcare collaboration revenue (2): ( in millions ): 2010
cost-sharing of regeneron vegf trap-eye development expenses: 45.5
substantive performance milestone payments: 20
recognition of deferred revenue related to up-front and other milestone payments: 9.9
total bayer healthcare collaboration revenue: 75.4
: ( in millions ): 2009
cost-sharing of regeneron vegf trap-eye development expenses: 37.4
substantive performance milestone payments: 20
recognition of deferred revenue related to up-front and other milestone payments: 9.9
total bayer healthcare collaboration revenue: 67.3

cost-sharing of our vegf trap-eye development expenses with bayer healthcare increased in 2010 compared to 2009 due to higher internal development activities and higher clinical development costs in connection with our phase 3 copernicus trial in crvo . in the fourth quarter of 2010 , we earned two $ 10.0 million substantive milestone payments from bayer healthcare for achieving positive 52-week results in the view 1 study and positive 6-month results in the copernicus study . in july 2009 , we earned a $ 20.0 million substantive performance milestone payment from bayer healthcare in connection with the dosing of the first patient in the copernicus study . in connection with the recognition of deferred revenue related to the $ 75.0 million up-front payment and $ 20.0 million milestone payment received in august 2007 , as of december 31 , 2010 , $ 47.0 million of these payments was deferred and will be recognized as revenue in future periods . technology licensing revenue in connection with our velocimmune ae license agreements with astrazeneca and astellas , each of the $ 20.0 million annual , non-refundable payments were deferred upon receipt and recognized as revenue ratably over approximately the ensuing year of each agreement . in both 2010 and 2009 , we recognized $ 40.0 million of technology licensing revenue related to these agreements . in addition , in connection with the amendment and extension of our license agreement with astellas , in august 2010 , we received a $ 165.0 million up-front payment , which was deferred upon receipt and will be recognized as revenue ratably over a seven-year period beginning in mid-2011 . as of december 31 , 2010 , $ 176.6 million of these technology licensing payments was deferred and will be recognized as revenue in future periods . net product sales in 2010 and 2009 , we recognized as revenue $ 25.3 million and $ 18.4 million , respectively , of arcalyst ae net product sales for which both the right of return no longer existed and rebates could be reasonably estimated . the company had limited historical return experience for arcalyst ae beginning with initial sales in 2008 through the end of 2009 ; therefore , arcalyst ae net product sales were deferred until the right of return no longer existed and rebates could be reasonably estimated . effective in the first quarter of 2010 , the company determined that it had .

Questions:
what was the change in the total bayer healthcare collaboration revenue from 2009 to 2010?
and what was that revenue in 2009?
how much, then, does that change represent in relation to this 2009 revenue, in percentage?

Answers:
8.1
67.3
12%