condition mean min max ZT0-3 4.305562568 1.418410208 7.192714928 ZT4-7 11.8546538275 11.40292049 12.306387165 ZT8-11 21.381701281999998 14.945026559 27.818376004999998 ZT12-15 52.3474539825 52.229339350000004 52.465568614999995 ZT16-19 38.58190853000001 36.54264989000001 40.62116717 ZT20-23 35.77483916 35.31632084 36.23335748