|
| year | consumption | change |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | 4.17 | NA |
| 1987 | 4.36 | 4.62 % |
| 1988 | 3.89 | -10.77 % |
| 1989 | 4.28 | 10.09 % |
| 1990 | 4.33 | 1.18 % |
| 1991 | 4.20 | -3.14 % |
| 1992 | 2.80 | -33.17 % |
| 1993 | 2.87 | 2.47 % |
| 1994 | 3.14 | 9.21 % |
| 1995 | 3.03 | -3.45 % |
| 1996 | 2.86 | -5.69 % |
| 1997 | 2.88 | 0.64 % |
| 1998 | 3.34 | 15.98 % |
| 1999 | 3.07 | -7.99 % |
| 2000 | 4.10 | 33.58 % |
| 2001 | 4.59 | 12.04 % |
| 2002 | 4.66 | 1.48 % |
| 2003 | 5.57 | 19.50 % |
| 2004 | 5.70 | 2.25 % |
| 2005 | 6.07 | 6.64 % |
| 2006 | 5.31 | -12.65 % |
| 2007 | 3.46 | -34.70 % |
| 2008 | 3.61 | 4.22 % |
| 2009 | 3.79 | 5.08 % |
| 2010 | 4.08 | 7.45 % |
|
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