|
| year | consumption | change |
| 1980 | .71 | NA |
| 1981 | .83 | 17.26 % |
| 1982 | .93 | 11.93 % |
| 1983 | 1.05 | 13.41 % |
| 1984 | 1.15 | 9.43 % |
| 1985 | 1.21 | 5.39 % |
| 1986 | 1.24 | 2.65 % |
| 1987 | 1.30 | 4.23 % |
| 1988 | 1.30 | 0.34 % |
| 1989 | 1.35 | 3.57 % |
| 1990 | 1.44 | 6.64 % |
| 1991 | 1.43 | -0.37 % |
| 1992 | 1.43 | -0.39 % |
| 1993 | 1.37 | -3.90 % |
| 1994 | 1.56 | 13.48 % |
| 1995 | 1.59 | 2.02 % |
| 1996 | 1.73 | 8.77 % |
| 1997 | 1.79 | 3.62 % |
| 1998 | 1.85 | 3.32 % |
| 1999 | 1.92 | 3.98 % |
| 2000 | 2.01 | 4.28 % |
| 2001 | 2.23 | 10.97 % |
| 2002 | 2.26 | 1.46 % |
| 2003 | 2.43 | 7.77 % |
| 2004 | 2.58 | 6.14 % |
| 2005 | 2.69 | 4.14 % |
| 2006 | 2.54 | -5.62 % |
| 2007 | 2.71 | 6.76 % |
| 2008 | 3.19 | 17.85 % |
| 2009 | 3.20 | 0.30 % |
| 2010 | 3.31 | 3.25 % |
|
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