| Previous KI/KP Tx | Year | |||||||||
| 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 | 2001 | 2002 | |
| Total | 23,497 | 25,852 | 29,050 | 32,310 | 35,585 | 38,772 | 41,292 | 44,719 | 47,830 | 50,855 |
| No | 17,972 | 19,822 | 22,470 | 25,258 | 28,226 | 30,983 | 33,173 | 36,377 | 39,032 | 41,393 |
| Yes | 5,525 | 6,030 | 6,580 | 7,052 | 7,359 | 7,789 | 8,119 | 8,342 | 8,798 | 9,462 |
| Total (%) | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% |
| No | 76.5% | 76.7% | 77.3% | 78.2% | 79.3% | 79.9% | 80.3% | 81.3% | 81.6% | 81.4% |
| Yes | 23.5% | 23.3% | 22.7% | 21.8% | 20.7% | 20.1% | 19.7% | 18.7% | 18.4% | 18.6% |