condition mean min max ZT0-3 25.13755 18.61755 28.515549999999998 ZT4-7 11.08266 11.08266 11.08266 ZT8-11 12.397400000000001 12.397400000000001 12.397400000000001 ZT12-15 17.3612 14.8321 19.8903 ZT16-19 23.06695 23.06695 23.06695 ZT20-23 31.87285 31.87285 31.87285