condition mean min max ZT0-3 27.3 27.3 27.3 ZT4-7 42.5 42.5 42.5 ZT8-11 49.550000000000004 49.550000000000004 49.550000000000004 ZT12-15 7.199999999999999 7.199999999999999 7.199999999999999 ZT16-19 28.6 28.6 28.6 ZT20-23 74.95 74.95 74.95