condition mean min max ZT0-3 34.8 34.8 34.8 ZT4-7 44.5 44.5 44.5 ZT8-11 14.899999999999999 14.899999999999999 14.899999999999999 ZT12-15 13.049999999999999 13.049999999999999 13.049999999999999 ZT16-19 30.349999999999998 30.349999999999998 30.349999999999998 ZT20-23 16.75 16.75 16.75