|
| year | consumption | change |
| 1980 | | NA |
| 1981 | | NA |
| 1982 | | NA |
| 1983 | | NA |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | | NA |
| 1987 | | NA |
| 1988 | | NA |
| 1989 | | NA |
| 1990 | | NA |
| 1991 | | NA |
| 1992 | .33 | NA |
| 1993 | .19 | -41.67 % |
| 1994 | .15 | -18.99 % |
| 1995 | .15 | -2.55 % |
| 1996 | .16 | 5.22 % |
| 1997 | .16 | 2.99 % |
| 1998 | .17 | 1.12 % |
| 1999 | .14 | -12.85 % |
| 2000 | .14 | -4.54 % |
| 2001 | .13 | -8.24 % |
| 2002 | .15 | 17.54 % |
| 2003 | .13 | -10.42 % |
| 2004 | .14 | 2.12 % |
| 2005 | .15 | 11.67 % |
| 2006 | .14 | -8.03 % |
| 2007 | .17 | 19.46 % |
| 2008 | .17 | 4.34 % |
| 2009 | .18 | 2.20 % |
| 2010 | .19 | 8.10 % |
|
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