condition mean min max ZT0-3 11.074471 11.074471 11.074471 ZT4-7 10.881206500000001 10.881206500000001 10.881206500000001 ZT8-11 10.8466645 10.8466645 10.8466645 ZT12-15 9.2939765 9.2939765 9.2939765 ZT16-19 11.2241255 11.2241255 11.2241255 ZT20-23 12.607345500000001 12.607345500000001 12.607345500000001