condition mean min max ZT0-3 32.88643333333333 15.3578 42.39405 ZT4-7 6.593205 6.593205 6.593205 ZT8-11 8.69065 8.69065 8.69065 ZT12-15 19.581175 15.1126 24.04975 ZT16-19 25.28955 25.28955 25.28955 ZT20-23 36.64765 36.64765 36.64765