condition mean min max ZT0-3 0.758575 0.0 1.51715 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 0.58009125 0.0 1.1601825 ZT16-19 0.9057183333333333 0.0 1.8114366666666666 ZT20-23 0 0 0