condition mean min max ZT0-3 5.0332975 4.215205 5.85139 ZT4-7 4.768985 4.768985 4.768985 ZT8-11 5.17922 5.17922 5.17922 ZT12-15 0 0 0 ZT16-19 7.53519 7.53519 7.53519 ZT20-23 8.330465 8.330465 8.330465