|
| year | consumption | change |
| 1980 | 2.52 | NA |
| 1981 | 2.19 | -13.10 % |
| 1982 | 2.72 | 24.20 % |
| 1983 | 2.80 | 2.94 % |
| 1984 | 2.22 | -20.71 % |
| 1985 | 2.23 | 0.65 % |
| 1986 | 2.62 | 17.31 % |
| 1987 | 2.83 | 7.99 % |
| 1988 | 3.34 | 17.84 % |
| 1989 | 3.76 | 12.83 % |
| 1990 | 4.50 | 19.61 % |
| 1991 | 5.08 | 12.90 % |
| 1992 | 4.04 | -20.47 % |
| 1993 | 5.40 | 33.51 % |
| 1994 | 5.40 | 0.00 % |
| 1995 | 6.16 | 14.23 % |
| 1996 | 6.15 | -0.27 % |
| 1997 | 6.16 | 0.27 % |
| 1998 | 6.27 | 1.70 % |
| 1999 | 6.27 | 0.00 % |
| 2000 | 6.34 | 1.09 % |
| 2001 | 6.35 | 0.27 % |
| 2002 | 6.53 | 2.75 % |
| 2003 | 6.81 | 4.33 % |
| 2004 | 6.62 | -2.84 % |
| 2005 | 6.89 | 4.16 % |
| 2006 | 6.95 | 0.88 % |
| 2007 | 6.71 | -3.52 % |
| 2008 | 6.21 | -7.46 % |
| 2009 | 5.46 | -12.11 % |
| 2010 | 6.49 | 18.98 % |
| 2011 | | NA |
|
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