condition mean min max ZT0-3 0.7970408333333333 0.4872605 1.3702619999999999 ZT4-7 0.7512205000000001 0.7512205000000001 0.7512205000000001 ZT8-11 1.0055450000000001 1.0055450000000001 1.0055450000000001 ZT12-15 1.50421175 1.0576335 1.95079 ZT16-19 2.08284 2.08284 2.08284 ZT20-23 1.637735 1.637735 1.637735