|
| year | consumption | change |
| 1980 | | NA |
| 1981 | | NA |
| 1982 | | NA |
| 1983 | | NA |
| 1984 | | NA |
| 1985 | 2.25 | NA |
| 1986 | 1.98 | -12.04 % |
| 1987 | 2.24 | 13.35 % |
| 1988 | 2.42 | 7.84 % |
| 1989 | 2.47 | 2.26 % |
| 1990 | 2.54 | 2.75 % |
| 1991 | 2.81 | 10.36 % |
| 1992 | 2.75 | -1.87 % |
| 1993 | 3.32 | 20.60 % |
| 1994 | 3.48 | 4.73 % |
| 1995 | 3.48 | 0.00 % |
| 1996 | 3.47 | -0.27 % |
| 1997 | 3.48 | 0.27 % |
| 1998 | 3.48 | 0.00 % |
| 1999 | 3.48 | 0.00 % |
| 2000 | 3.53 | 1.52 % |
| 2001 | 3.53 | 0.00 % |
| 2002 | 3.53 | 0.00 % |
| 2003 | 3.53 | 0.00 % |
| 2004 | 3.53 | 0.00 % |
| 2005 | 3.53 | 0.00 % |
| 2006 | 3.93 | 11.35 % |
| 2007 | 4.69 | 19.23 % |
| 2008 | 4.90 | 4.51 % |
| 2009 | 4.76 | -2.78 % |
| 2010 | 4.76 | 0.00 % |
| 2011 | | NA |
|
|