Sample Size
Size of sample needed to yield error of 5% or less in 95 out of 100 samples
Population Size |
Obtained Sample Size |
Percent of
Population |
50 | 45 | 90 |
100 | 80 | 80 |
200 | 132 | 66 |
300 | 168 | 56 |
400 | 196 | 49 |
500 | 218 | 43 |
600 | 234 | 39 |
800 | 240 | 32 |
1,000 | 278 | 27 |
2,000 | 323 | 16 |
3,000 | 341 | 11 |
5,000 | 357 | 7 |
6,000 | 361 | 6 |
8,000 | 367 | 4 |
10,000 | 370 | 3 |
15,000 | 375 | 2 |
20,000 | 377 | 1.8 |
30,000 | 379 | 1.2 |
50,000 | 381 | 0.7 |
75,000 | 382 | 0.4 |
100,000 | 383 | 0.03 |
Source: Michigan State Univeristy OMERAD Medical Education Section