Interest rates, especially low-interest rates, are often used by central banks to encourage borrowing and spending. In the United States, the Federal Reserve has kept interest rates near zero since the 2008 financial crisis in an effort to stimulate the economy. In Europe, the European Central Bank has also kept interest rates low in an effort to boost growth. Historically, banks have taken deposits from customers and used those deposits, along with their own capital, to make loans to businesses and individuals. The interest rate charged on these loans is typically higher than the interest rate paid on deposits, and the difference between the two rates is known as the net interest margin. When interest rates are low, banks' net interest margins are squeezed, as they are paying more interest on deposits than they are earning on loans. To offset the impact of low interest rates on their profitability, banks have been taking on more risk in recent years. They have been making more loans to high-risk borrowers, and they have also been investing in more risky assets, such as private equity and hedge funds. This has led to concerns that banks are becoming too risky. In an effort to address these concerns, regulators have been taking steps to increase the amount of capital that banks are required to hold. This will make banks less likely to fail in the event of a financial crisis. However, it will also make it more difficult for banks to lend money, which could further slow economic growth. ```