The size of Bank of Japan's balance sheet is fast approaching Japan's GDP, as BoJ has spent more than a year buying up government debt (primarily to meet a 2% inflation target). For context, the Federal Reserve balance sheet represents less than one quarter of U.S. GDP.

Why it matters: Local economists to worry about what will happen to BoJ when long-term interest rates eventually begin to rise, lowering the value of the central bank's holdings but spiking its interest rate payments. And while we don't yet have Q3 GDP data for Japan, we do know that BoJ assets continued to grow.