|
| year | consumption | change |
| 1980 | .06 | NA |
| 1981 | .06 | 3.16 % |
| 1982 | .06 | -2.45 % |
| 1983 | .06 | 9.91 % |
| 1984 | .06 | -3.62 % |
| 1985 | .06 | 0.41 % |
| 1986 | .06 | -1.85 % |
| 1987 | .06 | 10.71 % |
| 1988 | .07 | 8.30 % |
| 1989 | .08 | 8.52 % |
| 1990 | .07 | -1.83 % |
| 1991 | .08 | 6.64 % |
| 1992 | .09 | 17.22 % |
| 1993 | .10 | 4.95 % |
| 1994 | .10 | 5.46 % |
| 1995 | .11 | 2.89 % |
| 1996 | .11 | 1.11 % |
| 1997 | .12 | 10.70 % |
| 1998 | .12 | 2.56 % |
| 1999 | .13 | 9.79 % |
| 2000 | .14 | 5.66 % |
| 2001 | .15 | 3.20 % |
| 2002 | .15 | 5.34 % |
| 2003 | .16 | 4.07 % |
| 2004 | .16 | 2.76 % |
| 2005 | .16 | -1.27 % |
| 2006 | .17 | 7.99 % |
| 2007 | .18 | 5.41 % |
| 2008 | .19 | 3.32 % |
| 2009 | .18 | -2.99 % |
| 2010 | .19 | 1.35 % |
|
|