condition mean min max ZT0-3 28.9973 28.9973 28.9973 ZT4-7 24.6155 24.6155 24.6155 ZT8-11 18.125700000000002 18.125700000000002 18.125700000000002 ZT12-15 21.680999999999997 21.680999999999997 21.680999999999997 ZT16-19 26.466533333333334 26.466533333333334 26.466533333333334 ZT20-23 30.8172 30.8172 30.8172