condition mean min max ZT0-3 13.219813 13.219813 13.219813 ZT4-7 12.658243 12.658243 12.658243 ZT8-11 12.658243 12.658243 12.658243 ZT12-15 12.338655 12.338655 12.338655 ZT16-19 13.337416000000001 13.337416000000001 13.337416000000001 ZT20-23 13.7299755 13.7299755 13.7299755