|
| year | consumption | change |
| 1980 | .86 | NA |
| 1981 | .87 | 1.16 % |
| 1982 | .87 | 0.00 % |
| 1983 | .87 | 0.00 % |
| 1984 | .90 | 3.45 % |
| 1985 | .89 | -0.61 % |
| 1986 | .89 | -0.05 % |
| 1987 | .89 | 0.00 % |
| 1988 | .89 | -0.27 % |
| 1989 | .89 | 0.27 % |
| 1990 | .93 | 4.08 % |
| 1991 | .93 | 0.00 % |
| 1992 | .95 | 1.68 % |
| 1993 | .95 | 0.27 % |
| 1994 | .95 | 0.00 % |
| 1995 | .97 | 1.92 % |
| 1996 | .96 | -0.27 % |
| 1997 | .97 | 0.27 % |
| 1998 | .97 | 0.00 % |
| 1999 | .97 | 0.00 % |
| 2000 | .96 | -0.22 % |
| 2001 | .97 | 0.27 % |
| 2002 | 1.01 | 4.13 % |
| 2003 | 1.01 | 0.00 % |
| 2004 | 1.02 | 1.53 % |
| 2005 | 1.05 | 2.56 % |
| 2006 | 1.03 | -2.23 % |
| 2007 | 1.04 | 1.78 % |
| 2008 | 1.04 | 0.00 % |
| 2009 | 1.08 | 3.00 % |
| 2010 | 1.08 | 0.00 % |
| 2011 | | NA |
|
|