condition mean min max ZT0-3 4.601999999999999 4.601999999999999 4.601999999999999 ZT4-7 13.90915 13.90915 13.90915 ZT8-11 6.553305 6.553305 6.553305 ZT12-15 1.2444359999999999 1.2444359999999999 1.2444359999999999 ZT16-19 5.24664 5.24664 5.24664 ZT20-23 5.816906666666666 5.816906666666666 5.816906666666666