condition mean min max ZT0-3 25.021225 23.4256 26.61685 ZT4-7 19.38325 19.38325 19.38325 ZT8-11 17.13375 17.13375 17.13375 ZT12-15 0 0 0 ZT16-19 20.353299999999997 20.353299999999997 20.353299999999997 ZT20-23 25.143349999999998 25.143349999999998 25.143349999999998