ディフュージョンインデックスMeanings1noundiffusion indexEconomic indicator that measures the breadth of change across components, often used in business cycle analysis.景けい気き動どう向こう指し数すうのディフュージョンインデックスが50を超こえると、景けい気き拡かく大だいを示しめす。When the diffusion index of the business conditions index exceeds 50, it indicates economic expansion.