|
| 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 | .31 | NA |
| 1993 | .27 | -13.13 % |
| 1994 | .29 | 6.08 % |
| 1995 | .30 | 6.01 % |
| 1996 | .30 | -2.01 % |
| 1997 | .31 | 2.66 % |
| 1998 | .28 | -8.26 % |
| 1999 | .32 | 13.27 % |
| 2000 | .40 | 26.20 % |
| 2001 | .50 | 25.22 % |
| 2002 | .58 | 16.38 % |
| 2003 | .76 | 29.89 % |
| 2004 | .81 | 6.30 % |
| 2005 | .83 | 3.14 % |
| 2006 | .84 | 1.08 % |
| 2007 | .90 | 6.95 % |
| 2008 | .93 | 3.56 % |
| 2009 | .89 | -4.87 % |
| 2010 | .92 | 4.13 % |
|
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