|
| year | consumption | change |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | 2.10 | NA |
| 1987 | 1.94 | -7.78 % |
| 1988 | 1.98 | 2.13 % |
| 1989 | 1.99 | 0.27 % |
| 1990 | 2.03 | 2.35 % |
| 1991 | 2.01 | -1.15 % |
| 1992 | 2.00 | -0.27 % |
| 1993 | 1.99 | -0.89 % |
| 1994 | 1.99 | 0.00 % |
| 1995 | 1.87 | -5.88 % |
| 1996 | 1.86 | -0.27 % |
| 1997 | 1.87 | 0.27 % |
| 1998 | 1.75 | -6.25 % |
| 1999 | 1.75 | 0.00 % |
| 2000 | 1.75 | -0.27 % |
| 2001 | 1.75 | 0.27 % |
| 2002 | 1.90 | 8.25 % |
| 2003 | 2.06 | 8.79 % |
| 2004 | 2.07 | 0.49 % |
| 2005 | 2.41 | 16.05 % |
| 2006 | 3.31 | 37.58 % |
| 2007 | 3.39 | 2.33 % |
| 2008 | 1.64 | -51.72 % |
| 2009 | 1.40 | -14.29 % |
| 2010 | 1.33 | -5.00 % |
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