Year	Biodiesel	Ethanol	Electric	Liquefied Petroleum Gas	Natural Gas	Plug-in hybrids	All alternative fuel cars
2000	0	0	0	0	0.1	0	13.5
2001	0	0	0	1.8	0.1	0	14.8
2002	0	0	0	4.9	4.3	0	15.9
2003	0	0	0.1	2.3	13.1	0	15.5
2004	0	0	0.1	3.3	19.9	0	23.3
2005	0	0	0	11.6	25.5	0	37
2006	0	0	0	34.8	14.4	0	49.2
2007	0	0	0	89.9	21.7	0	111.6
2008	0	0	0	161.5	22.9	0	184.5
2009	0	1.2	0.2	498	17.9	0	517.3
2010	0.1	13.2	7	359.3	78.6	0	458.1
2011	0.1	25.6	5.9	85.4	51.8	0	168.8
2012	0	21.6	15.4	162.2	65.3	0	264.5
2013	0	4.4	24.2	130.5	81.6	31.1	271.7
2014	0	3.3	38	142.6	91.3	68.5	343.8