condition mean min max ZT0-3 9.474098333333334 5.79105 11.95025 ZT4-7 8.687495 8.687495 8.687495 ZT8-11 3.553915 3.553915 3.553915 ZT12-15 5.4890175 4.1820900000000005 6.795945 ZT16-19 7.026645 7.026645 7.026645 ZT20-23 8.46617 8.46617 8.46617