condition mean min max ZT0-3 1.5136612500000002 1.1468125 1.8805100000000001 ZT4-7 2.072585 2.072585 2.072585 ZT8-11 3.117865 3.117865 3.117865 ZT12-15 0 0 0 ZT16-19 3.6977349999999998 3.6977349999999998 3.6977349999999998 ZT20-23 2.179335 2.179335 2.179335