| Year | New | Existing | Total |
| Programs | Programs | ||
| 1962 | 1 | 0 | 1 |
| 1971 | 1 | 1 | 2 |
| 1972 | 0 | 2 | 2 |
| 1973 | 0 | 2 | 2 |
| 1974 | 2 | 2 | 4 |
| 1975 | 2 | 4 | 6 |
| 1976 | 0 | 6 | 6 |
| 1977 | 0 | 6 | 6 |
| 1978 | 0 | 6 | 6 |
| 1979 | 1 | 6 | 7 |
| 1980 | 1 | 7 | 8 |
| 1981 | 1 | 8 | 9 |
| 1982 | 5 | 9 | 14 |
| 1983 | 2 | 14 | 16 |
| 1984 | 1 | 16 | 17 |
| 1985 | 1 | 17 | 18 |
| 1986 | 5 | 18 | 23 |
| 1987 | 1 | 23 | 24 |
| 1988 | 2 | 24 | 26 |
| 1989 | 3 | 26 | 29 |
| 1990 | 6 | 29 | 35 |
| 1991 | 8 | 35 | 43 |
| 1992 | 15 | 43 | 58 |
| 1993 | 12 | 58 | 70 |
| 1994 | 7 | 70 | 77 |
| 1995 | 21 | 77 | 98 |
| 1996 | 26 | 98 | 124 |
| 1997 | 25 | 124 | 149 |
| 1998 | 28 | 149 | 177 |
| 1999 | 25 | 177 | 202 |
| 2000 | 30 | 202 | 232 |
| 2001 | 25 | 232 | 257 |
| 2002 | 11 | 257 | 268 |
| 2003 | 14 | 268 | 282 |
| 2004 | 22 | 282 | 304 |
| 2005 | 10 | 304 | 314 |
| 2006 | 10 | 314 | 324 |
| 2007 | 6 | 324 | 330 |
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