The number of country A forces in country B decreased to approximately 34,000 in 2014 from a high of about 100,000 in 2009. The amount of country A funding for country B security forces also decreased during this period. The function f(x) = - 1.369x2 +5.224x +5.517 can be used to estimate the amount of country A funding for country B security forces, in billions of dollars, x years after January 2008. In what year was the amount of country A funding for country B security forces about $10.5 billion? The amount of country A funding for country B security forces was about $10.5 billion in the year (Round down to the nearest year) ​