condition mean min max ZT0-3 13.793597 13.793597 13.793597 ZT4-7 13.2859835 13.2859835 13.2859835 ZT8-11 13.8998975 13.8998975 13.8998975 ZT12-15 13.5307685 13.5307685 13.5307685 ZT16-19 13.541372500000001 13.541372500000001 13.541372500000001 ZT20-23 14.1001125 14.1001125 14.1001125