condition mean min max ZT0-3 7.974869548999999 7.39902942 8.550709677999999 ZT4-7 4.1764467495 4.124916809 4.22797669 ZT8-11 4.34045949375 4.0312000045000005 4.649718983 ZT12-15 5.1229729302500004 4.772921587 5.4730242735 ZT16-19 5.165991304 4.435797287 5.896185321000001 ZT20-23 6.16472568475 6.0300937495 6.29935762