Monthly GDP rose 0.3% in August following a 0.2% increase in July that was revised lower by 0.2 percentage point. The increase in August reflected a large increase in domestic final sales that was partially offset by a decline in nonfarm inventory investment. The gain in domestic final sales, in turn, was led by a robust increase in nonresidential fixed investment; personal consumption expenditures posted a moderate gain. The level of GDP in August was 2.5% above the second-quarter average at an annual rate. Implicit in our forecast of 2.2% GDP growth in the third quarter is a 0.1% increase in monthly GDP in September.

Macroeconomic Advisers by IHS Markit's index of Monthly GDP (MGDP) is a monthly indicator of real aggregate output that is conceptually consistent with real Gross Domestic Product (GDP) in the National Income and Product Accounts. The Monthly GDP Index is consistent with the NIPAs for two reasons: first, MGDP is calculated using much of the same underlying monthly source data that is used in the calculation of GDP. Second, the method of aggregation to arrive at MGDP is similar to that for official GDP. Growth of MGDP at the monthly frequency is determined primarily by movements in the underlying monthly source data, and growth of MGDP at the quarterly frequency is nearly identical to growth of real GDP.

Posted 26 September 2019 by Ben Herzon, US Economist, Insights and Analysis, S&P Global Market Intelligence and

Kathleen Navin, Economics Executive Director, US Macroeconomics, S&P Global Market Intelligence