condition mean min max ZT0-3 22.1946 22.1946 22.1946 ZT4-7 17.2982 17.2982 17.2982 ZT8-11 18.497549999999997 18.497549999999997 18.497549999999997 ZT12-15 17.95645 17.95645 17.95645 ZT16-19 22.5261 22.5261 22.5261 ZT20-23 23.6837 23.6837 23.6837