condition mean min max ZT0-3 16.812283333333333 16.15615 18.0468 ZT4-7 9.95987 9.95987 9.95987 ZT8-11 6.478565 6.478565 6.478565 ZT12-15 8.448855 7.375845 9.521865 ZT16-19 7.109679999999999 7.109679999999999 7.109679999999999 ZT20-23 11.14275 11.14275 11.14275