condition mean min max ZT0-3 0.753924 0.7390595 0.7687885 ZT4-7 0.8631455 0.8631455 0.8631455 ZT8-11 2.17747 2.17747 2.17747 ZT12-15 0 0 0 ZT16-19 2.786345 2.786345 2.786345 ZT20-23 1.904215 1.904215 1.904215