| Group | N | Mean | Standard deviation | 95% Confidence Interval | Minimum | Maximum | |
|---|---|---|---|---|---|---|---|
| Lower Bound | Upper Bound | ||||||
| A | 24 | 277.4 | 32.5 | 263.7 | 291.2 | 215 | 335 |
| B | 28 | 283.4 | 24.5 | 273.8 | 292.9 | 218 | 338 |
| C | 27 | 314.0 | 28.6 | 302.7 | 325.3 | 251 | 360 |
| D | 85 | 318.7 | 22.4 | 313.9 | 323.6 | 245 | 364 |
| Total | 164 | 305.9 | 30.7 | 301.1 | 310.6 | 215 | 364 |