condition mean min max ZT0-3 237.1257926 210.31165529999998 263.93992990000004 ZT4-7 254.10178845 237.38036469999997 270.8232122 ZT8-11 152.06606015499997 112.28715655999999 191.84496374999998 ZT12-15 50.189348172500004 48.94043313 51.438263215 ZT16-19 73.1892934725 63.32011603 83.05847091499999 ZT20-23 89.403055765 88.59005072 90.21606081