condition mean min max ZT0-3 36.6674580725 31.354130505 41.98078564 ZT4-7 21.471910264999998 18.638836975 24.304983555 ZT8-11 30.504882450000004 24.93018958 36.079575320000004 ZT12-15 17.315829298 12.538825846 22.09283275 ZT16-19 8.405901477 8.209425667 8.602377287 ZT20-23 6.365834302 6.15405346 6.577615144