There is one vitally important number that everyone needs to be watching right now, and it doesn't have anything to do with unemployment, inflation or housing. If this number gets too high, it will collapse the entire U.S. financial system. The number that I am talking about is the yield on 10 year U.S. Treasuries. When that number goes up, long-term interest rates all across the financial system start increasing. When long-term interest rates rise, it becomes more expensive for the federal government to borrow money, it becomes more expensive for state and local governments to borrow money, existing bonds lose value and bond investors lose a lot of money, mortgage rates go up and monthly payments on new mortgages rise, and interest rates throughout the entire economy go up and this causes economic activity to slow down.