condition mean min max ZT0-3 18.757616666666667 17.23305 20.19375 ZT4-7 20.231099999999998 20.231099999999998 20.231099999999998 ZT8-11 21.9943 21.9943 21.9943 ZT12-15 25.080824999999997 23.63045 26.5312 ZT16-19 25.3263 25.3263 25.3263 ZT20-23 26.216050000000003 26.216050000000003 26.216050000000003