What it means
In the years before the crisis, lenders made many home loans to borrowers with weak credit or little proof of income, often on terms that became harder to meet over time. House prices were rising, so borrowers assumed they could sell or refinance if payments became difficult.
When prices fell, that assumption failed. Many homeowners found that they owed more than their home was worth, which is called negative equity.
Without equity, they could not sell to clear the loan, and they could not refinance. When interest rates on adjustable loans reset upwards or when jobs were lost, missed payments turned into foreclosures.
The impact spread through the financial system because mortgages had been bundled into securities and sold to investors around the world. As defaults rose, those securities lost value, and banks and insurers holding them reported heavy losses.
Credit tightened across the economy, hurting businesses that had nothing to do with housing. Governments and central banks responded with emergency lending, support for banks and programmes to help borrowers modify their loans.
Regulators later tightened lending standards, including rules requiring lenders to check that borrowers can afford their mortgages. For businesses, the crisis is a lasting case study in how a problem in one market can spread.
Finance teams still refer to it when talking about stress testing, counterparty risk (the chance the other side of a deal cannot pay) and the danger of assuming asset prices only rise. The effects reached well beyond the United States.
Banks in Europe and elsewhere had bought American mortgage securities, so losses and the loss of confidence travelled quickly across borders and added to the pressure on lenders everywhere.
In practice
Real-world examples.
Example
A construction company in a fast-growing region sees new home orders collapse as buyers cannot get mortgages. Its finance director cuts spending, renegotiates its credit line and delays two land purchases to preserve cash.
Example
A regional bank finds that 6% of its mortgage portfolio is more than 90 days overdue. It sets aside additional provisions for losses and writes to borrowers offering loan modifications where they can afford revised payments.
Example
An investor holding mortgage-backed securities discovers that the loans behind them are defaulting. The securities lose half their market value, and the fund's board orders a full review of its exposure to structured products. Each of these cases shows how one weak link in the chain can affect many businesses.
Formula
Calculation
Home equity = current market value - outstanding mortgage balance
Suppose a family buys a home for $400,000 with a $380,000 mortgage, so equity at purchase is $400,000 - $380,000 = $20,000. If prices fall 20%, the home is worth $400,000 x 0.80 = $320,000.
Equity = $320,000 - $380,000 = -$60,000. The family now owes $60,000 more than the home is worth, which is the negative equity that pushed many borrowers towards default.Case study
Seen in the real world.
Oakdale Community Bank is a fictional lender that made a large number of home loans during a boom. Its risk manager noticed that unemployment in the area was rising and that house prices had started to fall. She asked for a stress test of the mortgage book.
The test assumed prices falling 25% and unemployment doubling. In this illustrative scenario, it showed that losses could consume more than half of the bank's capital. The board responded by tightening new lending, raising capital and working with troubled borrowers early.
When the downturn came, Oakdale suffered losses but survived. Peer banks that had not stress tested their books were forced to seek emergency help or merge. The bank's chief executive later told staff that the discipline of imagining a bad outcome had been more valuable than any single forecast of good ones.
Watch out
Common mistakes.
- Blaming the crisis on a single cause, when it came from lending standards, rising prices, complex securities and weak oversight working together.
- Assuming that house prices never fall nationally, which was a common belief before the crisis.
- Thinking the crisis only affected homeowners, when it spread to banks, investors and the wider economy.
Questions
People also ask.
What is a foreclosure?
It is the legal process by which a lender takes ownership of a property after the borrower fails to keep up with loan payments. The lender then usually sells the property to recover what it is owed.
Why did foreclosures spread so fast?
Falling prices left borrowers with negative equity, so they could neither sell nor refinance, and many lost income at the same time.
What changed afterwards?
Lending rules became stricter, banks were required to hold more capital, and regulators began to run regular stress tests. Lenders also pay far more attention to proof of income and the borrower's ability to repay.
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