|
| year | consumption | change |
| 1980 | | NA |
| 1981 | | NA |
| 1982 | | NA |
| 1983 | | NA |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | | NA |
| 1987 | | NA |
| 1988 | | NA |
| 1989 | | NA |
| 1990 | | NA |
| 1991 | | NA |
| 1992 | 34.12 | NA |
| 1993 | 30.58 | -10.35 % |
| 1994 | 29.23 | -4.44 % |
| 1995 | 27.94 | -4.40 % |
| 1996 | 25.92 | -7.22 % |
| 1997 | 24.39 | -5.90 % |
| 1998 | 24.27 | -0.51 % |
| 1999 | 25.34 | 4.39 % |
| 2000 | 26.14 | 3.17 % |
| 2001 | 25.71 | -1.66 % |
| 2002 | 26.66 | 3.72 % |
| 2003 | 27.41 | 2.82 % |
| 2004 | 28.15 | 2.67 % |
| 2005 | 27.92 | -0.79 % |
| 2006 | 27.69 | -0.84 % |
| 2007 | 28.69 | 3.62 % |
| 2008 | 29.63 | 3.28 % |
| 2009 | 27.69 | -6.56 % |
| 2010 | 29.32 | 5.89 % |
|
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