condition mean min max ZT0-3 7.9972925 6.617805000000001 9.37678 ZT4-7 10.030535 10.030535 10.030535 ZT8-11 9.017085 9.017085 9.017085 ZT12-15 0 0 0 ZT16-19 13.52345 13.52345 13.52345 ZT20-23 8.89897 8.89897 8.89897