condition mean min max ZT0-3 26.618002 26.618002 26.618002 ZT4-7 27.2081845 27.2081845 27.2081845 ZT8-11 24.8669185 24.8669185 24.8669185 ZT12-15 23.822513999999998 23.822513999999998 23.822513999999998 ZT16-19 21.951335 21.951335 21.951335 ZT20-23 24.215031 24.215031 24.215031