condition mean min max ZT0-3 28.062504665 25.83850529 30.286504039999997 ZT4-7 29.864640155000004 27.452552943333334 32.27672736666667 ZT8-11 33.443833024999996 32.932965796666664 33.95470025333333 ZT12-15 27.54330539 27.03130034 28.055310440000003 ZT16-19 28.125579835 27.89440329 28.35675638 ZT20-23 23.435256091666666 21.77242513 25.098087053333334