condition mean min max ZT0-3 0.40670116666666667 0.25658749999999997 0.5501765000000001 ZT4-7 0.3562775 0.3562775 0.3562775 ZT8-11 0.36532149999999997 0.36532149999999997 0.36532149999999997 ZT12-15 0.702437 0.6976165 0.7072575 ZT16-19 0.219318 0.219318 0.219318 ZT20-23 0.576532 0.576532 0.576532