With prices quickly going up after the COVID-19 pandemic, inflation releases have rarely been as present in the public debate as in recent years. However, since inflation estimates are frequently revised, how precise are the real-time data releases? In this Liberty Street Economics post, we investigate the size and nature of revisions to inflation. We find that inflation estimates for a given month can change substantially as subsequent data vintages are released. As an example, consider March 2009. With the economy contracting amid the Global Financial Crisis, the twelve-month inflation rate for personal consumption ... (full story)