condition mean min max ZT0-3 1.1311563333333334 0.378921 2.348065 ZT4-7 4.540455 4.540455 4.540455 ZT8-11 2.02066 2.02066 2.02066 ZT12-15 2.0523575000000003 1.6063399999999999 2.4983750000000002 ZT16-19 0.8272569999999999 0.8272569999999999 0.8272569999999999 ZT20-23 0.5570305 0.5570305 0.5570305