condition mean min max ZT0-3 2.17957 1.7369500000000002 2.62219 ZT4-7 4.03485 4.03485 4.03485 ZT8-11 2.270135 2.270135 2.270135 ZT12-15 0 0 0 ZT16-19 2.94069 2.94069 2.94069 ZT20-23 4.053305 4.053305 4.053305