|
| year | consumption | change |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | 9.52 | NA |
| 1987 | 10.08 | 5.88 % |
| 1988 | 10.21 | 1.29 % |
| 1989 | 11.26 | 10.30 % |
| 1990 | 10.46 | -7.12 % |
| 1991 | 12.60 | 20.42 % |
| 1992 | 13.09 | 3.96 % |
| 1993 | 11.54 | -11.83 % |
| 1994 | 12.34 | 6.88 % |
| 1995 | 15.30 | 23.99 % |
| 1996 | 13.00 | -15.03 % |
| 1997 | 16.57 | 27.42 % |
| 1998 | 16.78 | 1.29 % |
| 1999 | 15.56 | -7.24 % |
| 2000 | 17.20 | 10.51 % |
| 2001 | 17.20 | 0.00 % |
| 2002 | 15.89 | -7.61 % |
| 2003 | 15.98 | 0.59 % |
| 2004 | 16.31 | 2.06 % |
| 2005 | | NA |
| 2006 | 17.99 | NA |
| 2007 | 19.16 | 6.49 % |
| 2008 | 18.93 | -1.22 % |
| 2009 | 20.26 | 7.04 % |
| 2010 | 20.75 | 2.42 % |
|
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