condition mean min max ZT0-3 22.400367455 20.060411119999998 24.74032379 ZT4-7 14.8688111125 13.873286185 15.86433604 ZT8-11 14.3089220575 13.29463848 15.323205635 ZT12-15 11.250773204 11.027562945 11.473983463 ZT16-19 13.8843121075 12.674123745 15.09450047 ZT20-23 17.012790787500002 16.851693765 17.173887810000004