condition mean min max ZT0-3 2.6837549999999997 2.53424 2.8332699999999997 ZT4-7 1.78369 1.78369 1.78369 ZT8-11 3.77285 3.77285 3.77285 ZT12-15 0 0 0 ZT16-19 3.907165 3.907165 3.907165 ZT20-23 3.86065 3.86065 3.86065