condition mean min max ZT0-3 5.03404 5.03404 5.03404 ZT4-7 4.74634 4.74634 4.74634 ZT8-11 4.6727050000000006 4.6727050000000006 4.6727050000000006 ZT12-15 5.33245 5.33245 5.33245 ZT16-19 3.979713333333333 3.979713333333333 3.979713333333333 ZT20-23 6.02412 6.02412 6.02412