|
| YEAR |
ANNUAL AVERAGE |
| 1969 |
3.95 |
| 1970 |
1.99 |
| 1971 |
1.42 |
| 1972 |
3.49 |
| 1973 |
2.12 |
| 1974 |
5.59 |
| 1975 |
5.70 |
| 1976 |
6.23 |
| 1977 |
1.41 |
| 1978 |
6.67 |
| 1979 |
4.45 |
| 1980 |
5.56 |
| 1981 |
9.99 |
| 1982 |
13.35 |
| 1983 |
14.99 |
| 1984 |
13.21 |
| 1985 |
14.14 |
| 1986 |
13.22 |
| 1987 |
12.86 |
| 1988 |
13.48 |
| 1989 |
13.99 |
| 1990 |
14.70 |
| 1991 |
16.30 |
| 1992 |
16.51 |
| 1993 |
44.39 |
| 1994 |
24.56 |
| 1995 |
18.17 |
| 1996 |
22.12 |
| 1997 |
22.50 |
| 1998 |
23.39 |
| 1999 |
15.01 |
| 2000 |
12.02 |
| 2001 |
12.73 |
| 2002 |
8.940 |
| 2003 |
3.670 |
| 2004 |
2.859 |
| 2005 |
8.437 |
| 2006 |
6.827 |
| 2007 |
6.827 |
| 2008 |
7.704 |
| 2009 |
7.387 |
| 2010 |
3.622 |
| 2011 |
8.696 |
|
|