condition mean min max ZT0-3 13.19675 13.07385 13.31965 ZT4-7 12.290500000000002 12.290500000000002 12.290500000000002 ZT8-11 12.8683 12.8683 12.8683 ZT12-15 0 0 0 ZT16-19 15.458400000000001 15.458400000000001 15.458400000000001 ZT20-23 13.71435 13.71435 13.71435