| Class | Date Established |
|---|---|
| 474 | 1980 |
| 475 | 1990 |
| 476 | 1993 |
| 477 | 1994 |
| 482 | 1992 |
| 483 | 1992 |
| 492 | 1993 |
| 493 | 1980 |
| 494 | 1982 |
| 501 | 1981 |
| 502 | 1983 |
| 503 | 1987 |
| 504 | 1993 |
| 505 | 1988 |
| 506 | 2007 |
| 507 | 1991 |
| 508 | 1996 |
| 510 | 1996 |
| 512 | 1987 |
| 514 | 1985 |
| 516 | 1998 |
| 518 | 1981 |
| 520 | 1982 |
| 521 | 1978 |
| 522 | 1986 |
| 523 | 1982 |
| 524 | 1982 |
| 525 | 1979 |
| 526 | 1976 |
| 527 | 1982 |
| 528 | 1976 |
| 530 | 1984 |
| 532 | 1984 |
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