|
| year | consumption | change |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | 4.27 | NA |
| 1987 | 4.77 | 11.92 % |
| 1988 | 5.06 | 6.00 % |
| 1989 | 5.31 | 5.00 % |
| 1990 | 5.07 | -4.66 % |
| 1991 | 5.41 | 6.80 % |
| 1992 | 6.05 | 11.80 % |
| 1993 | 6.69 | 10.62 % |
| 1994 | 7.68 | 14.71 % |
| 1995 | 7.02 | -8.55 % |
| 1996 | 8.45 | 20.41 % |
| 1997 | 8.91 | 5.44 % |
| 1998 | 8.11 | -9.01 % |
| 1999 | 8.13 | 0.29 % |
| 2000 | 7.03 | -13.50 % |
| 2001 | 6.49 | -7.78 % |
| 2002 | 5.14 | -20.75 % |
| 2003 | 5.82 | 13.18 % |
| 2004 | 4.92 | -15.49 % |
| 2005 | 5.87 | 19.28 % |
| 2006 | 4.51 | -23.11 % |
| 2007 | 5.80 | 28.50 % |
| 2008 | 6.95 | 19.92 % |
| 2009 | 6.52 | -6.19 % |
| 2010 | 9.23 | 41.58 % |
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