condition mean min max ZT0-3 10.984633 10.984633 10.984633 ZT4-7 9.760813 9.760813 9.760813 ZT8-11 10.9597555 10.9597555 10.9597555 ZT12-15 9.8734645 9.8734645 9.8734645 ZT16-19 10.1756915 10.1756915 10.1756915 ZT20-23 9.664043 9.664043 9.664043