condition mean min max ZT0-3 3.544365 3.544365 3.544365 ZT4-7 3.599875 3.599875 3.599875 ZT8-11 3.08929 3.08929 3.08929 ZT12-15 3.16383 3.16383 3.16383 ZT16-19 3.60903 3.60903 3.60903 ZT20-23 3.880495 3.880495 3.880495