condition mean min max ZT0-3 22.71765 22.71765 22.71765 ZT4-7 19.31995 19.31995 19.31995 ZT8-11 18.7843 18.7843 18.7843 ZT12-15 19.49705 19.49705 19.49705 ZT16-19 23.3185 23.3185 23.3185 ZT20-23 22.4824 22.4824 22.4824