condition mean min max ZT0-3 1.102139439 0.7561399120000001 1.448138966 ZT4-7 5.26054036 3.785466319 6.735614400999999 ZT8-11 8.497504558500001 8.019664978 8.975344139 ZT12-15 9.059333864500001 7.274381261 10.844286468 ZT16-19 5.1063171285 4.1499073385 6.062726918499999 ZT20-23 13.928388790249999 9.3740498005 18.482727779999998