condition mean min max ZT0-3 58.345135 58.345135 58.345135 ZT4-7 56.008649 56.008649 56.008649 ZT8-11 53.2783505 53.2783505 53.2783505 ZT12-15 49.103594 49.103594 49.103594 ZT16-19 42.2895535 42.2895535 42.2895535 ZT20-23 47.6815625 47.6815625 47.6815625