GDP Revisions: Measurement and Implications

Gauging economic conditions in real time is challenging, in part because economic data are difficult to measure and subject to subsequent revision as more information becomes available. This article investigates the pattern and size of revisions to real gross domestic product (GDP) over the past decade or so. Revisions to early estimates of GDP can be large and, over the past 15 years, have tended to increase measured growth, although the extent of revision is in line with international experience. This article also examines the feasibility of adjusting real-time estimates of GDP for apparent patterns in revisions, predicting future revisions and calculating confidence intervals around the historical data. The uncertainty around real-time GDP estimates highlights the importance of monitoring a wide range of information when assessing current economic conditions.