condition mean min max ZT0-3 1.4261925 1.213225 1.63916 ZT4-7 1.3851 1.3851 1.3851 ZT8-11 2.80767 2.80767 2.80767 ZT12-15 0 0 0 ZT16-19 2.5359350000000003 2.5359350000000003 2.5359350000000003 ZT20-23 2.308305 2.308305 2.308305