This page shows the size of G4 (U.S., euro area, UK and Japan) central banks' balance sheet since 2007. The blue dots show the timing of various U.S. quantitative easing programs introduced after the global financial crisis and the COVID-19 pandemic in 2020. The orange line shows the 12-month change in balance sheets and this illustrates the aggressive quantitative easing by central banks to combat the negative impact from the COVID-19 pandemic. One important takeaway is that central banks find it very difficult to reduce the size of the balance sheet even when the economy is growing. The only period where G4 balance sheets got smaller was in 2019, when the Federal Reserve actively reversed its quantitative easing by selling its securities holdings back to the market.