condition mean min max ZT0-3 5.264185 5.264185 5.264185 ZT4-7 4.473375 4.473375 4.473375 ZT8-11 4.538035 4.538035 4.538035 ZT12-15 5.281325000000001 5.281325000000001 5.281325000000001 ZT16-19 5.975355 5.975355 5.975355 ZT20-23 4.925275 4.925275 4.925275