condition mean min max ZT0-3 5.230098333333333 3.60934 8.055865 ZT4-7 2.581435 2.581435 2.581435 ZT8-11 5.044205 5.044205 5.044205 ZT12-15 5.195235 3.54373 6.8467400000000005 ZT16-19 3.50866 3.50866 3.50866 ZT20-23 6.99891 6.99891 6.99891