| JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | TOTALS | % CHANGE | ||
| 2008 | 8 | 8 | 4 | 20 | 0.1% | DECREASE | |||||||||
| 2007 | 2 | 9 | 11 | 6 | 4 | 7 | 10 | 4 | 8 | 3 | 8 | 3 | 75 | 8.5% | DECREASE |
| 2006 | 2 | 1 | 3 | 7 | 8 | 7 | 12 | 15 | 8 | 5 | 3 | 11 | 82 | 100.0% | INCREASE |
| 2005 | 3 | 4 | 3 | 5 | 4 | 2 | 3 | 7 | 2 | 4 | 3 | 1 | 41 | 29.3% | DECREASE |
| 2004 | 4 | 4 | 6 | 7 | 5 | 4 | 6 | 8 | 3 | 3 | 4 | 4 | 58 | 56.8% | INCREASE |
| 2003 | 3 | 0 | 0 | 6 | 2 | 4 | 5 | 7 | 0 | 5 | 3 | 2 | 37 | 35.1% | DECREASE |
| 2002 | 4 | 6 | 5 | 6 | 5 | 4 | 10 | 1 | 11 | 2 | 3 | 0 | 57 | 26.7% | INCREASE |
| 2001 | 4 | 8 | 5 | 0 | 1 | 4 | 6 | 5 | 4 | 3 | 3 | 2 | 45 | 18.2% | DECREASE |
| 2000 | 3 | 2 | 3 | 9 | 7 | 4 | 7 | 3 | 4 | 6 | 3 | 4 | 55 | 10.0% | INCREASE |
| 1999 | 4 | 6 | 1 | 3 | 3 | 5 | 4 | 3 | 4 | 6 | 8 | 3 | 50 | 5.7% | DECREASE |
| 1998 | 4 | 3 | 7 | 0 | 5 | 6 | 3 | 5 | 7 | 4 | 5 | 4 | 53 | 0.0% | DECREASE |
| 1997 | 4 | 4 | 8 | 1 | 4 | 5 | 4 | 7 | 5 | 4 | 2 | 5 | 53 | 10.2% | DECREASE |
| 1996 | 3 | 8 | 2 | 2 | 9 | 7 | 4 | 2 | 10 | 5 | 4 | 3 | 59 | 5.4% | INCREASE |
| 1995 | 3 | 7 | 5 | 2 | 7 | 4 | 4 | 2 | 5 | 9 | 5 | 3 | 56 | 15.2% | DECREASE |
| 1994 | 5 | 3 | 2 | 3 | 8 | 6 | 11 | 11 | 5 | 1 | 9 | 2 | 66 | 6.5% | INCREASE |
| 1993 | 3 | 4 | 6 | 5 | 4 | 10 | 10 | 6 | 1 | 5 | 3 | 5 | 62 | 59.0% | INCREASE |
| 1992 | 4 | 6 | 8 | 4 | 5 | 2 | 3 | 8 | 7 | 2 | 2 | 4 | 39 | 29.1% | DECREASE |
| 1991 | 2 | 4 | 4 | 5 | 4 | 7 | 4 | 5 | 2 | 7 | 8 | 3 | 55 | 20.3% | DECREASE |
| 1990 | 4 | 4 | 4 | 8 | 5 | 8 | 12 | 9 | 1 | 1 | 9 | 4 | 69 | 64.3% | INCREASE |
| 1989 | 3 | 2 | 1 | 4 | 4 | 5 | 3 | 4 | 1 | 4 | 8 | 3 | 42 | 17.6% | DECREASE |
| 1988 | 5 | 6 | 8 | 6 | 3 | 3 | 7 | 6 | 2 | 1 | 3 | 1 | 51 | 10.5% | DECREASE |
| 1987 | 6 | 2 | 7 | 5 | 6 | 9 | 2 | 4 | 7 | 3 | 3 | 3 | 57 | 0.0% | DECREASE |
| 1986 | 10 | 3 | 2 | 5 | 4 | 4 | 3 | 3 | 10 | 9 | 2 | 2 | 57 | 35.7% | INCREASE |
| 1985 | 2 | 1 | 2 | 4 | 4 | 4 | 5 | 9 | 3 | 3 | 1 | 4 | 42 | 34.4% | DECREASE |
| 1984 | 4 | 5 | 3 | 9 | 6 | 4 | 4 | 8 | 7 | 4 | 9 | 1 | 64 | 33.3% | INCREASE |
| 1983 | 3 | 3 | 4 | 1 | 4 | 7 | 8 | 7 | 2 | 3 | 3 | 3 | 48 | 29.4% | DECREASE |
| 1982 | 6 | 9 | 5 | 2 | 5 | 2 | 8 | 8 | 7 | 6 | 7 | 3 | 68 | 5.6% | DECREASE |
| 1981 | 6 | 3 | 3 | 3 | 13 | 12 | 4 | 8 | 7 | 9 | 2 | 2 | 72 | 41.2% | INCREASE |
| 1980 | 3 | 2 | 2 | 7 | 8 | 3 | 5 | 3 | 4 | 1 | 10 | 3 | 51 | 13.3% | INCREASE |
| 1979 | 2 | 5 | 6 | 3 | 3 | 6 | 4 | 2 | 3 | 4 | 4 | 3 | 45 | 16.7% | DECREASE |
| 1978 | 2 | 3 | 7 | 3 | 8 | 4 | 6 | 6 | 5 | 2 | 3 | 5 | 54 | 21.7% | DECREASE |
| 1977 | 3 | 7 | 9 | 5 | 6 | 6 | 7 | 7 | 4 | 8 | 2 | 5 | 69 | 5.5% | DECREASE |
| 1976 | 7 | 7 | 4 | 7 | 9 | 4 | 6 | 9 | 4 | 4 | 5 | 7 | 73 | 1.4% | DECREASE |
| 1975 | 3 | 2 | 11 | 3 | 4 | 7 | 9 | 9 | 13 | 4 | 4 | 5 | 74 | 19.4% | INCREASE |
| 1974 | 0 | 5 | 2 | 8 | 5 | 9 | 4 | 8 | 8 | 6 | 4 | 3 | 62 | 63.2% | INCREASE |
| 1973 | 0 | 0 | 6 | 1 | 4 | 9 | 4 | 2 | 1 | 1 | 5 | 5 | 38 | 11.8% | INCREASE |
| 1972 | 0 | 2 | 3 | 3 | 3 | 6 | 4 | 3 | 5 | 0 | 5 | 0 | 34 |