|
| year | consumption | change |
| 1980 | 10.00 | NA |
| 1981 | 10.00 | 0.00 % |
| 1982 | | NA |
| 1983 | | NA |
| 1984 | | NA |
| 1985 | 6.30 | NA |
| 1986 | 6.84 | 8.54 % |
| 1987 | 7.20 | 5.23 % |
| 1988 | 6.72 | -6.60 % |
| 1989 | 7.41 | 10.24 % |
| 1990 | 7.58 | 2.21 % |
| 1991 | 8.22 | 8.44 % |
| 1992 | 8.63 | 5.10 % |
| 1993 | 8.66 | 0.27 % |
| 1994 | 8.42 | -2.77 % |
| 1995 | 8.42 | 0.00 % |
| 1996 | 8.60 | 2.17 % |
| 1997 | 8.62 | 0.27 % |
| 1998 | 8.68 | 0.70 % |
| 1999 | 8.68 | 0.00 % |
| 2000 | 8.59 | -1.11 % |
| 2001 | 8.61 | 0.27 % |
| 2002 | 10.02 | 16.30 % |
| 2003 | 10.02 | 0.00 % |
| 2004 | 11.37 | 13.55 % |
| 2005 | 11.42 | 0.45 % |
| 2006 | 13.78 | 20.65 % |
| 2007 | 13.94 | 1.13 % |
| 2008 | 13.82 | -0.87 % |
| 2009 | 14.55 | 5.31 % |
| 2010 | 14.55 | 0.00 % |
| 2011 | 15.00 | 3.10 % |
|
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