condition mean min max ZT0-3 5.9486099999999995 4.733035 6.979189999999999 ZT4-7 3.9797900000000004 3.9797900000000004 3.9797900000000004 ZT8-11 4.5805050000000005 4.5805050000000005 4.5805050000000005 ZT12-15 5.8916474999999995 5.7271149999999995 6.0561799999999995 ZT16-19 6.08609 6.08609 6.08609 ZT20-23 8.561215 8.561215 8.561215