condition mean min max ZT0-3 16.904171666666667 9.355865 27.433999999999997 ZT4-7 0.0 0.0 0.0 ZT8-11 0.0 0.0 0.0 ZT12-15 4.780355 4.53381 5.0269 ZT16-19 0.0 0.0 0.0 ZT20-23 4.953295 4.953295 4.953295