|
| year | consumption | change |
| 1980 | 1.10 | NA |
| 1981 | 2.50 | 127.27 % |
| 1982 | 2.40 | -4.00 % |
| 1983 | 2.70 | 12.50 % |
| 1984 | 4.43 | 64.04 % |
| 1985 | 4.50 | 1.60 % |
| 1986 | 4.47 | -0.74 % |
| 1987 | 4.54 | 1.58 % |
| 1988 | 4.58 | 0.95 % |
| 1989 | 4.71 | 2.77 % |
| 1990 | 4.87 | 3.53 % |
| 1991 | 4.94 | 1.33 % |
| 1992 | 5.07 | 2.71 % |
| 1993 | 4.61 | -9.07 % |
| 1994 | 4.70 | 1.84 % |
| 1995 | 4.77 | 1.65 % |
| 1996 | 4.76 | -0.27 % |
| 1997 | 4.84 | 1.70 % |
| 1998 | 4.92 | 1.67 % |
| 1999 | 4.92 | 0.00 % |
| 2000 | 5.19 | 5.38 % |
| 2001 | 5.24 | 1.04 % |
| 2002 | 5.27 | 0.45 % |
| 2003 | 5.33 | 1.18 % |
| 2004 | 5.16 | -3.05 % |
| 2005 | 5.50 | 6.43 % |
| 2006 | 5.62 | 2.30 % |
| 2007 | 5.13 | -8.85 % |
| 2008 | 5.10 | -0.52 % |
| 2009 | 5.30 | 3.99 % |
| 2010 | 5.28 | -0.49 % |
| 2011 | | NA |
|
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