condition mean min max ZT0-3 18.0907 17.091 19.0904 ZT4-7 14.48835 14.48835 14.48835 ZT8-11 14.833499999999999 14.833499999999999 14.833499999999999 ZT12-15 0 0 0 ZT16-19 22.20015 22.20015 22.20015 ZT20-23 22.7054 22.7054 22.7054