condition mean min max ZT0-3 636.468466 636.468466 636.468466 ZT4-7 364.0647495 364.0647495 364.0647495 ZT8-11 510.04659399999997 510.04659399999997 510.04659399999997 ZT12-15 528.143687 528.143687 528.143687 ZT16-19 942.878915 942.878915 942.878915 ZT20-23 819.7370245 819.7370245 819.7370245