| 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 | 2 | 26 | 28 |
| 1990 | 6 | 28 | 34 |
| 1991 | 8 | 34 | 42 |
| 1992 | 15 | 42 | 57 |
| 1993 | 12 | 57 | 69 |
| 1994 | 7 | 69 | 76 |
| 1995 | 21 | 76 | 97 |
| 1996 | 27 | 97 | 124 |
| 1997 | 25 | 124 | 149 |
| 1998 | 29 | 149 | 178 |
| 1999 | 25 | 178 | 203 |
| 2000 | 30 | 203 | 233 |
| 2001 | 25 | 233 | 258 |
| 2002 | 11 | 258 | 269 |
| 2003 | 16 | 269 | 285 |
| 2004 | 22 | 285 | 307 |
| 2005 | 10 | 307 | 317 |
| 2006 | 11 | 317 | 328 |
| 2007 | 7 | 328 | 335 |
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