condition mean min max ZT0-3 7.129615 7.129615 7.129615 ZT4-7 56.5781 56.5781 56.5781 ZT8-11 41.63695 41.63695 41.63695 ZT12-15 10.535685 10.535685 10.535685 ZT16-19 2.29753 2.29753 2.29753 ZT20-23 2.316445 2.316445 2.316445