| Year | Total | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
| 1998 | 18 | 7 | 6 | 3 | 1 | 1 | |||||||
| 1997 | 3 | 3 | |||||||||||
| 1996 | 13 | 2 | 1 | 3 | 2 | 1 | 1 | 1 | 1 | 1 | |||
| 1995 | 11 | 1 | 1 | 1 | 3 | 2 | 1 | 1 | 1 | ||||
| 1994 | 14 | 4 | 1 | 2 | 1 | 2 | 3 | 1 | |||||
| 1993 | 20 | 1 | 2 | 2 | 3 | 3 | 2 | 4 | 3 | ||||
| 1992 | 21 | 4 | 4 | 4 | 3 | 4 | 1 | 1 | |||||
| 1991 | 39 | 3 | 3 | 4 | 3 | 4 | 4 | 4 | 4 | 3 | 4 | 2 | 1 |
| 1990 | 50 | 9 | 6 | 11 | 11 | 1 | 3 | 2 | 2 | 5 | |||
| 1989 | 147 | 19 | 4 | 14 | 17 | 13 | 4 | 22 | 7 | 8 | 21 | 13 | 5 |
| 1988 | 133 | 8 | 15 | 16 | 4 | 9 | 22 | 8 | 9 | 19 | 9 | 14 | |
| 1987 | 111 | 10 | 10 | 9 | 10 | 3 | 2 | 16 | 12 | 12 | 11 | 15 | 1 |
| 1986 | 113 | 1 | 22 | 16 | 10 | 25 | 15 | 10 | 2 | 4 | 8 | ||
| 1985 | 129 | 15 | 6 | 20 | 15 | 18 | 13 | 23 | 1 | 11 | 6 | 1 | |
| 1984 | 101 | 4 | 9 | 15 | 11 | 5 | 11 | 15 | 15 | 10 | 3 | 3 | |
| 1983 | 69 | 5 | 4 | 9 | 5 | 18 | 16 | 2 | 4 | 6 | |||
| 1982 | 31 | 9 | 18 | 4 | |||||||||
| 1981 | 1 | 1 | |||||||||||
| 1024 |
