condition mean min max ZT0-3 14.7425 14.03765 15.44735 ZT4-7 15.22055 15.22055 15.22055 ZT8-11 18.4992 18.4992 18.4992 ZT12-15 0 0 0 ZT16-19 20.7472 20.7472 20.7472 ZT20-23 19.544649999999997 19.544649999999997 19.544649999999997