condition mean min max ZT0-3 2.8227598333333335 1.0190795000000001 4.011045 ZT4-7 1.027852 1.027852 1.027852 ZT8-11 1.8942800000000002 1.8942800000000002 1.8942800000000002 ZT12-15 1.866425 1.7849249999999999 1.947925 ZT16-19 3.3181700000000003 3.3181700000000003 3.3181700000000003 ZT20-23 3.968845 3.968845 3.968845