|
| year | consumption | change |
| 1980 | 52.00 | NA |
| 1981 | 57.00 | 9.62 % |
| 1982 | 51.50 | -9.65 % |
| 1983 | 58.90 | 14.37 % |
| 1984 | 57.00 | -3.23 % |
| 1985 | 55.00 | -3.51 % |
| 1986 | 61.32 | 11.50 % |
| 1987 | 52.25 | -14.79 % |
| 1988 | 60.50 | 15.78 % |
| 1989 | 63.63 | 5.17 % |
| 1990 | 63.19 | -0.68 % |
| 1991 | 68.17 | 7.87 % |
| 1992 | 71.22 | 4.48 % |
| 1993 | 73.68 | 3.45 % |
| 1994 | 74.77 | 1.49 % |
| 1995 | 70.02 | -6.36 % |
| 1996 | 73.29 | 4.67 % |
| 1997 | 78.18 | 6.68 % |
| 1998 | 80.66 | 3.17 % |
| 1999 | 79.29 | -1.70 % |
| 2000 | 84.55 | 6.63 % |
| 2001 | 87.22 | 3.16 % |
| 2002 | 87.86 | 0.74 % |
| 2003 | 87.66 | -0.23 % |
| 2004 | 89.40 | 1.99 % |
| 2005 | 89.93 | 0.60 % |
| 2006 | 88.32 | -1.79 % |
| 2007 | 88.44 | 0.13 % |
| 2008 | 91.69 | 3.68 % |
| 2009 | 87.13 | -4.98 % |
| 2010 | 87.65 | 0.60 % |
| 2011 | 93.00 | 6.10 % |
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