January GDP Index

Monthly GDP slipped 0.1% in January following a 0.1% increase in December that was revised down one-tenth. The January decline reflected subtractions from residential investment, PCE, and net exports that were partially offset by an increase in nonfarm inventory investment.

The level of monthly GDP in January was 0.7% above the fourth-quarter average at an annual rate. Implicit in our forecast of 1.8% (annualized) growth of real GDP in the first quarter are increases in monthly GDP in February and March of 0.3% and 0.2%, respectively.

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.