Table 3. Estimated and imputed year-to-year retention rates (Y2YRR) and cumulative retention rates by year for authors based on start year and number of continuous publishing years*.
| Start year | ||||||||
| #Years UCP | Y2YRR | 1997 | 1998 | 1999 | 2000 | 2001 | 2002 | 2003 |
| 2 | 28.54% | 28.53% | 29.12% | 29.42% | 29.35% | 30.06% | 31.78% | |
| 3 | 14.93% | 15.08% | 15.62% | 15.87% | 16.09% | 16.88% | 18.25% | |
| 4 | 9.66% | 9.73% | 10.17% | 10.51% | 10.91% | 11.56% | 12.49% | |
| 5 | 6.90% | 6.98% | 7.40% | 7.85% | 8.21% | 8.73% | 9.41% | |
| 6 | 5.30% | 5.42% | 5.86% | 6.32% | 6.55% | 6.97% | 7.53% | |
| 7 | 4.32% | 4.47% | 4.87% | 5.29% | 5.50% | 5.80% | 6.25% | |
| 8 | 3.67% | 3.84% | 4.20% | 4.56% | 4.74% | 4.97% | 5.34% | |
| 9 | 3.24% | 3.39% | 3.70% | 4.04% | 4.16% | 4.35% | 4.62% | |
| 10 | 88% | 2.91% | 3.05% | 3.33% | 3.62% | 3.73% | 3.81% | 4.06% |
| 11 | 89% | 2.66% | 2.77% | 3.03% | 3.28% | 3.31% | 3.39% | 3.61% |
| 12 | 90% | 2.44% | 2.55% | 2.78% | 2.96% | 2.98% | 3.05% | 3.25% |
| 13 | 91% | 2.27% | 2.36% | 2.53% | 2.70% | 2.71% | 2.78% | 2.96% |
| 14 | 92% | 2.10% | 2.17% | 2.33% | 2.48% | 2.49% | 2.56% | 2.72% |
| 15 | 92% | 1.93% | 2.00% | 2.14% | 2.28% | 2.29% | 2.36% | 2.50% |
| 16 | 92% | 1.78% | 1.84% | 1.97% | 2.10% | 2.11% | 2.17% | 2.30% |
| UCP-16 births | 16877 | 17402 | 18657 | 20840 | 22301 | 23934 | 26562 | |
*Retention rates for future years that have been estimated using year-to-year retention rates (Y2YRR) from the earlier data are shown in bold type. Estimated (by extrapolation) numbers of authors who will have uninterrupted, continuous presence for 16 years (UCP-16-births) are listed at the bottom by start year.