condition mean min max ZT0-3 0.617136 0.4129545 0.8213175 ZT4-7 0.6849864999999999 0.6849864999999999 0.6849864999999999 ZT8-11 0.206123 0.206123 0.206123 ZT12-15 0 0 0 ZT16-19 2.2338699999999996 2.2338699999999996 2.2338699999999996 ZT20-23 1.018452 1.018452 1.018452