|
| year | consumption | change |
| 1980 | | NA |
| 1981 | | NA |
| 1982 | .90 | NA |
| 1983 | | NA |
| 1984 | | NA |
| 1985 | .90 | NA |
| 1986 | 1.13 | 24.82 % |
| 1987 | 1.43 | 26.24 % |
| 1988 | 1.49 | 4.47 % |
| 1989 | 1.70 | 14.38 % |
| 1990 | 1.67 | -1.82 % |
| 1991 | 1.59 | -5.05 % |
| 1992 | 1.50 | -5.79 % |
| 1993 | .82 | -44.99 % |
| 1994 | .86 | 4.86 % |
| 1995 | .58 | -33.14 % |
| 1996 | .58 | -0.27 % |
| 1997 | .39 | -31.52 % |
| 1998 | .46 | 16.30 % |
| 1999 | .46 | 0.00 % |
| 2000 | .50 | 9.26 % |
| 2001 | .46 | -8.47 % |
| 2002 | .46 | 0.00 % |
| 2003 | .50 | 8.92 % |
| 2004 | .54 | 8.48 % |
| 2005 | .56 | 2.80 % |
| 2006 | .56 | 1.22 % |
| 2007 | .58 | 3.63 % |
| 2008 | .58 | 0.00 % |
| 2009 | .58 | 0.00 % |
| 2010 | .58 | 0.00 % |
| 2011 | | NA |
|
|