The doubling time in years is approximately … being the percentage of interest
| i | doubling time | 4x time | 1024x time |
|---|---|---|---|
| 1 | 70 | 140 | 700 |
| 2 | 35 | 70 | 350 |
| 3 | 22.3 | 44.6 | 226 |
| 4 | 17.5 | 35 | 175 |
| 5 | 14 | 28 | 140 |
| 6 | 11.7 | 23.4 | 117 |
| 7 | 10 | 20 | 100 |
| 8 | 8.75 | 17.5 | 87.5 |
| 9 | 7.8 | 15.6 | 78 |
| 10 | 7 | 14 | 70 |
| 15 | 4.7 | 9.4 | 47 |
| 20 | 3.5 | 7 | 35 |
| 25 | 2.8 | 5.6 | 28 |
| 30 | 2.3 | 4.6 | 23 |