| Year | Rank | Number |
| 2002 | 16617 | 5 |
| 1996 | 14485 | 5 |
| 1992 | 12411 | 6 |
| 1989 | 13250 | 5 |
| 1988 | 8723 | 8 |
| 1987 | 10410 | 6 |
| 1985 | 9810 | 6 |
| 1983 | 6398 | 10 |
| 1981 | 9558 | 6 |
| 1980 | 9559 | 6 |
| 1979 | 10837 | 5 |
| 1978 | 7223 | 8 |
| 1976 | 5755 | 10 |
| 1975 | 9637 | 5 |
| 1974 | 8097 | 6 |
| 1973 | 6958 | 7 |
| 1971 | 6245 | 8 |
| 1970 | 6019 | 8 |
| 1969 | 5651 | 8 |
| 1968 | 7473 | 5 |
| 1967 | 7209 | 5 |
| 1966 | 6988 | 5 |
| 1965 | 6092 | 6 |
| 1963 | 7038 | 5 |
| 1961 | 5526 | 7 |
| 1951 | 5767 | 5 |
| 1950 | 5638 | 5 |