|
| 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 | 33.00 | NA |
| 1993 | 40.00 | 21.21 % |
| 1994 | 43.00 | 7.50 % |
| 1995 | 48.00 | 11.63 % |
| 1996 | 56.00 | 16.67 % |
| 1997 | 55.00 | -1.79 % |
| 1998 | 52.00 | -5.45 % |
| 1999 | 52.00 | 0.00 % |
| 2000 | 50.16 | -3.54 % |
| 2001 | 52.09 | 3.85 % |
| 2002 | 50.55 | -2.97 % |
| 2003 | 51.26 | 1.42 % |
| 2004 | 52.43 | 2.28 % |
| 2005 | 53.68 | 2.39 % |
| 2006 | 55.57 | 3.51 % |
| 2007 | 55.08 | -0.88 % |
| 2008 | 63.72 | 15.69 % |
| 2009 | 55.39 | -13.07 % |
| 2010 | 54.78 | -1.09 % |
| 2011 | 55.15 | 0.68 % |
|
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