condition mean min max ZT0-3 10.7601725 7.702945 13.8174 ZT4-7 5.143895 5.143895 5.143895 ZT8-11 8.5235 8.5235 8.5235 ZT12-15 0 0 0 ZT16-19 19.6619 19.6619 19.6619 ZT20-23 11.18836 11.18836 11.18836