|
| year | consumption | change |
| 1980 | 1.04 | NA |
| 1981 | .98 | -6.19 % |
| 1982 | 1.12 | 15.16 % |
| 1983 | 1.16 | 3.38 % |
| 1984 | 1.23 | 5.45 % |
| 1985 | 1.33 | 8.83 % |
| 1986 | 1.50 | 12.28 % |
| 1987 | 1.66 | 10.53 % |
| 1988 | 1.70 | 2.93 % |
| 1989 | 1.80 | 5.80 % |
| 1990 | 1.97 | 9.44 % |
| 1991 | 2.06 | 4.63 % |
| 1992 | 2.13 | 3.05 % |
| 1993 | 2.33 | 9.42 % |
| 1994 | 2.23 | -4.21 % |
| 1995 | 2.49 | 11.67 % |
| 1996 | 2.75 | 10.36 % |
| 1997 | 2.93 | 6.49 % |
| 1998 | 2.99 | 2.33 % |
| 1999 | 2.91 | -2.96 % |
| 2000 | 3.16 | 8.85 % |
| 2001 | 2.89 | -8.50 % |
| 2002 | 3.15 | 8.71 % |
| 2003 | 3.32 | 5.45 % |
| 2004 | 3.51 | 5.87 % |
| 2005 | 3.73 | 6.33 % |
| 2006 | 4.07 | 9.01 % |
| 2007 | 4.46 | 9.44 % |
| 2008 | 4.29 | -3.70 % |
| 2009 | 4.30 | 0.15 % |
| 2010 | 4.49 | 4.50 % |
|
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