| Class | Date Established |
|---|---|
| 427 | 1975 |
| 428 | 1975 |
| 429 | 1976 |
| 430 | 1979 |
| 431 | 1968 |
| 432 | 1972 |
| 433 | 1979 |
| 434 | 1980 |
| 435 | 1979 |
| 436 | 1982 |
| 438 | 1997 |
| 439 | 1987 |
| 440 | 1980 |
| 441 | 1982 |
| 442 | 1997 |
| 445 | 1983 |
| 446 | 1984 |
| 449 | 1988 |
| 450 | 1987 |
| 451 | 1994 |
| 452 | 1990 |
| 453 | 1987 |
| 454 | 1991 |
| 455 | 1980 |
| 460 | 1989 |
| 462 | 1991 |
| 463 | 1996 |
| 464 | 1982 |
| 470 | 1992 |
| 472 | 1992 |
| 473 | 1993 |
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