condition mean min max ZT0-3 2.42948 2.4184900000000003 2.44047 ZT4-7 2.29932 2.29932 2.29932 ZT8-11 2.20765 2.20765 2.20765 ZT12-15 0 0 0 ZT16-19 3.34098 3.34098 3.34098 ZT20-23 3.046035 3.046035 3.046035