condition mean min max ZT0-3 39.379911 39.379911 39.379911 ZT4-7 29.828709500000002 29.828709500000002 29.828709500000002 ZT8-11 25.7342385 25.7342385 25.7342385 ZT12-15 28.208594 28.208594 28.208594 ZT16-19 31.644388 31.644388 31.644388 ZT20-23 30.2034605 30.2034605 30.2034605