condition mean min max ZT0-3 1.885515 1.76736 2.00367 ZT4-7 1.760235 1.760235 1.760235 ZT8-11 1.8748850000000001 1.8748850000000001 1.8748850000000001 ZT12-15 0 0 0 ZT16-19 7.237305 7.237305 7.237305 ZT20-23 3.256965 3.256965 3.256965