|
| year | consumption | change |
| 1980 | 1.52 | NA |
| 1981 | 2.25 | 48.03 % |
| 1982 | | NA |
| 1983 | | NA |
| 1984 | | NA |
| 1985 | 5.23 | NA |
| 1986 | 6.57 | 25.73 % |
| 1987 | 6.64 | 0.97 % |
| 1988 | 6.59 | -0.75 % |
| 1989 | 6.56 | -0.47 % |
| 1990 | 6.26 | -4.56 % |
| 1991 | 6.15 | -1.74 % |
| 1992 | 5.97 | -2.86 % |
| 1993 | 5.87 | -1.75 % |
| 1994 | 4.71 | -19.66 % |
| 1995 | 4.87 | 3.23 % |
| 1996 | 4.85 | -0.27 % |
| 1997 | 4.87 | 0.27 % |
| 1998 | 4.87 | 0.00 % |
| 1999 | 4.87 | 0.00 % |
| 2000 | 4.58 | -5.96 % |
| 2001 | 4.59 | 0.27 % |
| 2002 | 4.82 | 5.14 % |
| 2003 | 5.73 | 18.86 % |
| 2004 | 5.68 | -0.99 % |
| 2005 | 6.27 | 10.45 % |
| 2006 | 6.70 | 6.86 % |
| 2007 | 6.61 | -1.34 % |
| 2008 | 7.25 | 9.60 % |
| 2009 | 6.99 | -3.48 % |
| 2010 | 7.19 | 2.81 % |
| 2011 | | NA |
|
|