condition mean min max ZT0-3 20.724624999999996 9.537075 30.002899999999997 ZT4-7 9.86826 9.86826 9.86826 ZT8-11 15.46675 15.46675 15.46675 ZT12-15 27.305 24.31675 30.29325 ZT16-19 30.2988 30.2988 30.2988 ZT20-23 34.5394 34.5394 34.5394