| Previous IN Tx | Year | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1998 | 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | |
| Total | 28 | 30 | 31 | 32 | 40 | 40 | 52 | 52 | 51 | 53 |
| No | 25 | 28 | 29 | 28 | 33 | 38 | 51 | 50 | 49 | 52 |
| Yes | 3 | 2 | 2 | 4 | 7 | 2 | 1 | 2 | 2 | 1 |
| Total (%) | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% |
| No | 89.3% | 93.3% | 93.5% | 87.5% | 82.5% | 95.0% | 98.1% | 96.2% | 96.1% | 98.1% |
| Yes | 10.7% | 6.7% | 6.5% | 12.5% | 17.5% | 5.0% | 1.9% | 3.8% | 3.9% | 1.9% |