|
| year | consumption | change |
| 1984 | | NA |
| 1985 | | NA |
| 1986 | .20 | NA |
| 1987 | .20 | 0.00 % |
| 1988 | .20 | 0.00 % |
| 1989 | .21 | 5.89 % |
| 1990 | .25 | 20.00 % |
| 1991 | .25 | 0.00 % |
| 1992 | .25 | -0.27 % |
| 1993 | .25 | 0.27 % |
| 1994 | .25 | 0.00 % |
| 1995 | .25 | -0.27 % |
| 1996 | .25 | 0.00 % |
| 1997 | .25 | 0.27 % |
| 1998 | .25 | 0.00 % |
| 1999 | .25 | 0.00 % |
| 2000 | .25 | -0.28 % |
| 2001 | .25 | 0.28 % |
| 2002 | .25 | 0.00 % |
| 2003 | .28 | 8.33 % |
| 2004 | .30 | 7.40 % |
| 2005 | .30 | 0.27 % |
| 2006 | .32 | 7.14 % |
| 2007 | .32 | 0.00 % |
| 2008 | .32 | 0.00 % |
| 2009 | .32 | 0.00 % |
| 2010 | .32 | 0.00 % |
|
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