condition mean min max ZT0-3 9.623106666666667 4.932415 16.01735 ZT4-7 14.0184 14.0184 14.0184 ZT8-11 8.201765 8.201765 8.201765 ZT12-15 7.0302325 6.859655 7.20081 ZT16-19 5.3877299999999995 5.3877299999999995 5.3877299999999995 ZT20-23 6.812035 6.812035 6.812035