condition mean min max ZT0-3 9.4161275 8.283005 10.54925 ZT4-7 13.4086 13.4086 13.4086 ZT8-11 16.5834 16.5834 16.5834 ZT12-15 0 0 0 ZT16-19 13.40025 13.40025 13.40025 ZT20-23 9.773695 9.773695 9.773695