|
| year | consumption | change |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | 7.68 | NA |
| 1987 | 9.10 | 18.54 % |
| 1988 | 9.78 | 7.44 % |
| 1989 | 8.58 | -12.25 % |
| 1990 | 10.73 | 25.09 % |
| 1991 | 8.47 | -21.05 % |
| 1992 | 11.51 | 35.79 % |
| 1993 | 14.55 | 26.44 % |
| 1994 | 14.55 | 0.03 % |
| 1995 | 12.49 | -14.17 % |
| 1996 | 16.82 | 34.64 % |
| 1997 | 14.16 | -15.82 % |
| 1998 | 17.93 | 26.67 % |
| 1999 | 19.01 | 6.04 % |
| 2000 | 16.99 | -10.66 % |
| 2001 | 14.59 | -14.10 % |
| 2002 | 14.99 | 2.71 % |
| 2003 | 15.48 | 3.28 % |
| 2004 | 15.46 | -0.13 % |
| 2005 | 15.91 | 2.92 % |
| 2006 | 18.65 | 17.21 % |
| 2007 | 20.50 | 9.93 % |
| 2008 | 29.44 | 43.62 % |
| 2009 | 24.51 | -16.74 % |
| 2010 | 21.51 | -12.26 % |
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