In the United States, the S&P Global Composite PMI Output Index, which is a weighted average of the Manufacturing Output Index and the Services Business Activity Index, tracks business trends across both manufacturing and service sectors. The index is based on data collected from a representative panel of over 800 companies and follows variables such as sales, new orders, employment, inventories and prices. A reading above 50 indicates expansion in business activity while below 50 points to contraction.