|
| year | consumption | change |
| 1980 | 9.80 | NA |
| 1981 | 9.59 | -2.12 % |
| 1982 | 9.21 | -4.00 % |
| 1983 | 9.19 | -0.18 % |
| 1984 | 9.78 | 6.47 % |
| 1985 | 10.15 | 3.76 % |
| 1986 | 10.25 | 1.00 % |
| 1987 | 10.59 | 3.23 % |
| 1988 | 11.05 | 4.42 % |
| 1989 | 11.20 | 1.33 % |
| 1990 | 10.98 | -1.97 % |
| 1991 | 11.12 | 1.25 % |
| 1992 | 11.46 | 3.08 % |
| 1993 | 11.70 | 2.12 % |
| 1994 | 12.02 | 2.73 % |
| 1995 | 12.21 | 1.59 % |
| 1996 | 12.55 | 2.77 % |
| 1997 | 12.65 | 0.76 % |
| 1998 | 12.35 | -2.40 % |
| 1999 | 12.97 | 5.05 % |
| 2000 | 13.30 | 2.60 % |
| 2001 | 12.87 | -3.25 % |
| 2002 | 13.10 | 1.74 % |
| 2003 | 13.53 | 3.28 % |
| 2004 | 14.11 | 4.35 % |
| 2005 | 14.17 | 0.41 % |
| 2006 | 13.82 | -2.50 % |
| 2007 | 14.03 | 1.50 % |
| 2008 | 13.55 | -3.42 % |
| 2009 | 13.10 | -3.32 % |
| 2010 | 13.00 | -0.74 % |
|
|