condition mean min max ZT0-3 7.065693333333334 3.338925 10.23703 ZT4-7 1.823766 1.823766 1.823766 ZT8-11 1.3973 1.3973 1.3973 ZT12-15 2.1880485 2.005017 2.37108 ZT16-19 3.111695 3.111695 3.111695 ZT20-23 6.037884999999999 6.037884999999999 6.037884999999999