condition mean min max ZT0-3 50.655146 50.655146 50.655146 ZT4-7 40.991999 40.991999 40.991999 ZT8-11 36.240125 36.240125 36.240125 ZT12-15 39.807926 39.807926 39.807926 ZT16-19 44.439045 44.439045 44.439045 ZT20-23 66.4900545 66.4900545 66.4900545