condition mean min max ZT0-3 33.26535 31.8029 34.7278 ZT4-7 24.00995 24.00995 24.00995 ZT8-11 17.23935 17.23935 17.23935 ZT12-15 0 0 0 ZT16-19 27.3504 27.3504 27.3504 ZT20-23 28.5556 28.5556 28.5556