According to two separate research studies conducted in 2009, at the national level 65% of the flex-fuel registered vehicles regularly used ethanol fuel, and the usage climbed to 93% in São Paulo, the main ethanol producer state where local taxes are lower, and prices at the pump are more competitive than gasoline. However, as a result of higher ethanol prices caused by the Brazilian ethanol industry crisis that began in 2009, combined with government subsidies to keep gasoline price lower than the international market value, by November 2013 only 23% flex-fuel car owners were using ethanol, down from 66% in 2009.