condition mean min max ZT0-3 8.1755825 8.101355 8.24981 ZT4-7 11.46945 11.46945 11.46945 ZT8-11 17.661450000000002 17.661450000000002 17.661450000000002 ZT12-15 0 0 0 ZT16-19 13.35005 13.35005 13.35005 ZT20-23 14.557749999999999 14.557749999999999 14.557749999999999