|
| 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 | .22 | NA |
| 1993 | .16 | -26.40 % |
| 1994 | .16 | -1.53 % |
| 1995 | .17 | 6.75 % |
| 1996 | .17 | -0.28 % |
| 1997 | .16 | -6.04 % |
| 1998 | .16 | -0.91 % |
| 1999 | .15 | -7.66 % |
| 2000 | .15 | 4.14 % |
| 2001 | .16 | 4.41 % |
| 2002 | .15 | -4.30 % |
| 2003 | .16 | 4.36 % |
| 2004 | .18 | 9.35 % |
| 2005 | .19 | 5.51 % |
| 2006 | .18 | -0.51 % |
| 2007 | .17 | -6.43 % |
| 2008 | .16 | -5.35 % |
| 2009 | .16 | 0.92 % |
| 2010 | .16 | -2.46 % |
|
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