condition mean min max ZT0-3 24.5503352925 23.21333373 25.887336855 ZT4-7 16.14762367 15.923070825 16.372176515 ZT8-11 22.495139082500003 18.578521205 26.41175696 ZT12-15 25.1466185525 24.09267957 26.200557534999998 ZT16-19 20.8247344375 20.23498553 21.414483345 ZT20-23 21.9020336075 21.436542695 22.36752452