|
| 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 | 1.53 | NA |
| 1993 | 1.24 | -18.70 % |
| 1994 | 1.08 | -13.47 % |
| 1995 | 1.01 | -6.13 % |
| 1996 | 1.01 | -0.04 % |
| 1997 | 1.00 | -1.34 % |
| 1998 | .98 | -1.98 % |
| 1999 | .99 | 1.08 % |
| 2000 | 1.05 | 6.62 % |
| 2001 | .96 | -8.50 % |
| 2002 | .91 | -5.74 % |
| 2003 | .98 | 8.50 % |
| 2004 | .95 | -3.33 % |
| 2005 | 1.12 | 18.10 % |
| 2006 | 1.15 | 2.70 % |
| 2007 | 1.15 | -0.26 % |
| 2008 | 1.12 | -2.70 % |
| 2009 | 1.05 | -6.17 % |
| 2010 | 1.13 | 7.62 % |
|
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