condition mean min max ZT0-3 8.932558333333333 6.870419999999999 12.5079 ZT4-7 7.7740149999999995 7.7740149999999995 7.7740149999999995 ZT8-11 8.468625 8.468625 8.468625 ZT12-15 12.94325 11.1369 14.749600000000001 ZT16-19 14.5904 14.5904 14.5904 ZT20-23 18.403 18.403 18.403