condition mean min max ZT0-3 32.926364 32.926364 32.926364 ZT4-7 39.630566 39.630566 39.630566 ZT8-11 27.7650215 27.7650215 27.7650215 ZT12-15 44.689462500000005 44.689462500000005 44.689462500000005 ZT16-19 29.7218835 29.7218835 29.7218835 ZT20-23 49.836157 49.836157 49.836157