| 3 Months | 1 Year | 3 Years | 5 Years | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| (Tx 2003 - 2004) | (Tx 2003 - 2004) | (Tx 2001 - 2004) | (Tx 1999 - 2004) | ||||||||||
| N | % | Std. Err. | N | % | Std. Err. | N | % | Std. Err. | N | % | Std. Err. | ||
| Total | All | 254 | 87.0% | 2.1% | 254 | 77.1% | 2.6% | 468 | 55.3% | 2.8% | 612 | 46.6% | 2.8% |
| Yearly Center Volume | 0-1 | 7 | 85.7% | 13.2% | 7 | 57.1% | 18.7% | 23 | 60.9% | 10.2% | 35 | 27.4% | 13.5% |
| 2-7 | 57 | 75.4% | 5.7% | 57 | 68.4% | 6.2% | 68 | 51.4% | 7.9% | 79 | 49.2% | 7.0% | |
| 8+ | 190 | 90.5% | 2.1% | 190 | 80.5% | 2.9% | 377 | 56.3% | 3.1% | 498 | 47.7% | 3.0% | |