$500 bn, but the effects of the subprime shock have been far reaching. In order to prevent such huge welfare losses, governments may intervene in the financial markets and implement policies to mitigate the effects of the initial financial shock. For the credit market view of the financial accelerator, one policy implementation is to break the link between borrower's net worth and its ability to borrow as shown in the figure above. There are various ways of breaking the mechanism of a financial accelerator. One way is to reverse the decline in the asset prices. When asset prices fall below a certain level, government can purchase assets at those prices, pulling up the demand for them and raising their prices back. The Federal Reserve was purchasing mortgage-backed securities in 2008 and 2009 with unusually low market prices. The supported asset prices pulls the net worth of the borrowers up, loosening the borrowing limits and stimulating investment. Financial accelerator in open economies The financial accelerator also exists in emerging market crises in the sense that adverse shocks to a small open economy may be amplified by worsening international financial market conditions. Now the link between the real economy and the international financial markets stems from the need for international borrowing; firms’ borrowing to engage in profitable investment and production opportunities, households’ borrowing to smooth consumption when faced with income volatility or even governments’ borrowing from international funds. Agents in an emerging economy often need external finance but informational frictions or limited commitment can limit their access to international capital markets. The information about the ability and willingness of a borrower to repay its debt is imperfectly observable so that the ability to borrow is often limited. The amount and terms of international borrowing depend on many conditions such as the credit history or default risk, output volatility or country risk, net worth or the value of collateralizable assets and the amount of outstanding liabilities. An initial shock to productivity, world interest rate or country risk premium may lead to a “sudden stop” of capital inflows which blocks economic activity, accelerating the initial downturn. Or the familiar story of “debt-deflation” amplifies the adverse effects of an asset price shock when agents are highly indebted and the market value of their collateralizable assets deflates dramatically. See also Accelerator effect References Corporate finance Business cycle theories