|
| year | consumption | change |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | .16 | NA |
| 1987 | .23 | 42.86 % |
| 1988 | .26 | 9.70 % |
| 1989 | .28 | 9.39 % |
| 1990 | .33 | 16.67 % |
| 1991 | .33 | 0.00 % |
| 1992 | .33 | -0.27 % |
| 1993 | .35 | 7.44 % |
| 1994 | .35 | 0.00 % |
| 1995 | .35 | 0.00 % |
| 1996 | .35 | -0.27 % |
| 1997 | .35 | 0.27 % |
| 1998 | .35 | 0.00 % |
| 1999 | .35 | 0.00 % |
| 2000 | .42 | 19.67 % |
| 2001 | .42 | 0.27 % |
| 2002 | .42 | 0.00 % |
| 2003 | .44 | 5.56 % |
| 2004 | .44 | -0.27 % |
| 2005 | .47 | 5.55 % |
| 2006 | .47 | 0.00 % |
| 2007 | .47 | 0.00 % |
| 2008 | .47 | 1.45 % |
| 2009 | .48 | 1.38 % |
| 2010 | .48 | 0.00 % |
|
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