condition mean min max ZT0-3 1.834715 1.699925 1.969505 ZT4-7 2.340115 2.340115 2.340115 ZT8-11 1.012229 1.012229 1.012229 ZT12-15 0 0 0 ZT16-19 1.295787 1.295787 1.295787 ZT20-23 1.69368 1.69368 1.69368