condition mean min max ZT0-3 14.2 14.2 14.2 ZT4-7 7.3 7.3 7.3 ZT8-11 10.65 10.65 10.65 ZT12-15 15.5 15.5 15.5 ZT16-19 14.899999999999999 14.899999999999999 14.899999999999999 ZT20-23 10.3 10.3 10.3