condition mean min max ZT0-3 17.1235 16.65865 17.58835 ZT4-7 17.582050000000002 17.582050000000002 17.582050000000002 ZT8-11 21.7565 21.7565 21.7565 ZT12-15 0 0 0 ZT16-19 27.021349999999998 27.021349999999998 27.021349999999998 ZT20-23 23.794400000000003 23.794400000000003 23.794400000000003