condition mean min max ZT0-3 1.269037 1.269037 1.269037 ZT4-7 1.0829365 1.0829365 1.0829365 ZT8-11 0.8562000000000001 0.8562000000000001 0.8562000000000001 ZT12-15 1.609005 1.609005 1.609005 ZT16-19 1.762165 1.762165 1.762165 ZT20-23 1.7052550000000002 1.7052550000000002 1.7052550000000002