NOₓ Emissions (thousand tons)					NOₓ Rate (lb/mmBtu)
Primary Fuel	2000	2005	2010	2020	2021	2000	2005	2010	2020	2021
Coal	NOₓ Emissions (thousand tons)	4,587	3,356	1,896	569	624	NOₓ Rate (lb/mmBtu)	0.44	0.32	0.20	0.14	0.13
Gas	NOₓ Emissions (thousand tons)	355	167	142	160	146	NOₓ Rate (lb/mmBtu)	0.18	0.06	0.04	0.03	0.03
Oil	NOₓ Emissions (thousand tons)	162	104	20	2	3	NOₓ Rate (lb/mmBtu)	0.31	0.25	0.13	0.10	0.20
Other	NOₓ Emissions (thousand tons)	2	6	5	6	6	NOₓ Rate (lb/mmBtu)	0.26	0.42	0.14	0.09	0.08
Total / Average	NOₓ Emissions (thousand tons)	5,104	3,633	2,063	737	779	NOₓ Rate (lb/mmBtu)	0.40	0.27	0.16	0.07	0.07