condition mean min max ZT0-3 992.3731666666666 466.11699999999996 1438.8 ZT4-7 226.406 226.406 226.406 ZT8-11 15.976949999999999 15.976949999999999 15.976949999999999 ZT12-15 25.216250000000002 17.96195 32.47055 ZT16-19 49.66515 49.66515 49.66515 ZT20-23 141.183 141.183 141.183