condition mean min max ZT0-3 22.81795 21.0295 24.0366 ZT4-7 16.92535 16.92535 16.92535 ZT8-11 16.29025 16.29025 16.29025 ZT12-15 31.048375 29.815800000000003 32.28095 ZT16-19 25.4657 25.4657 25.4657 ZT20-23 27.9327 27.9327 27.9327