condition mean min max ZT0-3 15.5691848925 14.96889448 16.169475305 ZT4-7 9.770621662 6.222182033999999 13.31906129 ZT8-11 6.338922973500001 5.372594986666667 7.305250960333334 ZT12-15 8.624083303833332 6.804339151 10.443827456666666 ZT16-19 6.8752854995 5.79030737 7.960263629 ZT20-23 8.249428977166666 8.100950011333333 8.397907943