condition mean min max ZT0-3 3.72209 1.9551500000000002 5.028295 ZT4-7 2.703135 2.703135 2.703135 ZT8-11 2.678 2.678 2.678 ZT12-15 6.152502500000001 4.984545000000001 7.320460000000001 ZT16-19 6.14102 6.14102 6.14102 ZT20-23 8.405975 8.405975 8.405975