A US homeowner misses a mortgage payment. You own a broad stock fund, with retailers and manufacturers alongside banks. Surely someone else's home loan is a distant problem.
Say you have $1,000 in that fund set aside for a $600 bill. Does owning many businesses make the money safe until the bill is due?
During the 2007–09 decline, the S&P 500 lost more than half its price value. Mortgage losses spread through institutions that borrowed heavily, then reached businesses with no home loans on their books.
The boom linked homes to finance
In the early 2000s, rising US home prices and easier mortgage lending fed each other. Subprime mortgages were loans to borrowers with weaker credit profiles. Lenders loosened their standards, sometimes making loans without checking income carefully. Rising house prices gave struggling borrowers an escape: sell or refinance.
The lender did not have to keep the loan. Mortgage securitization means pooling mortgages and selling claims on their payments. Those claims are mortgage-backed securities, or MBS. Investors' money helped finance the loans; homeowners' payments then flowed back through a company called a servicer.
Pooling could spread the risk of one borrower defaulting. It could not remove a housing slump affecting many borrowers at once. When house prices fell, selling a home could leave its mortgage unpaid, passing losses along the chain. Loan quality, payment rules and guarantees meant some MBS were safer than others.
Some lenders were rewarded for making more loans rather than better ones. Investors underestimated housing risk, and regulators failed to contain the buildup. Enron hid obligations it retained; here, even loans genuinely sold to new owners could spread losses through the financial system.
Losses met a thin cushion
The thin equity cushion from the 1929 example reappeared inside financial institutions. Heavy borrowing left some firms little room to absorb losses on mortgage assets.
Many also borrowed for short periods while their assets paid back over years. As each loan came due, they needed another loan to replace it. That worked only while lenders kept saying yes.
Funding liquidity is the ability to meet cash obligations when due. An institution could own assets that would pay over time and still lack the cash to survive Friday.
That cash shortage differs from a credit loss: money a borrower cannot repay. Selling an asset might raise the cash, but only if a buyer is available at a workable price. That ease of selling is market liquidity. In the crisis, all three problems fed each other.
Complex mortgage holdings made it hard to tell who could repay. Lenders did not need proof of a loss to pull back. Uncertainty itself could cut off funding.
A housing problem became a run
Lenders also worried about collateral: assets pledged as protection for a loan. As mortgage securities fell in value, lenders demanded more protection or refused to renew funding. Financial firms sold assets to raise cash. Those sales pushed prices lower, hurting other holders and alarming their lenders in turn.
One firm's attempt to survive became another firm's loss.
A funding run happens when short-term lenders rush to withdraw money or refuse to renew loans. Like the bank runs after 1929, it could leave an institution unable to pay. Much of this run happened through financial markets, without queues outside bank branches.
Funding strains emerged in August 2007. In spring 2008, JPMorgan Chase acquired Bear Stearns with Federal Reserve assistance. Lehman Brothers filed for bankruptcy that September, intensifying a crisis already underway.
The decline reached the broad market
A retailer did not need to own mortgage securities to suffer. Customers who lost wealth or jobs spent less. Businesses found credit harder to obtain, cut investment and reduced employment. Less lending and less spending reinforced each other.
Different companies still depended on the same flow of credit and customers' money.
The S&P 500 closed at 1,565.15 on October 9, 2007, then fell to a closing low of 676.53 on March 9, 2009. S&P Dow Jones Indices' historical table records both turning points.
The price decline was (1 − 676.53 ÷ 1,565.15) × 100 = 56.78%. That measures the full 2007–09 fall, not the calendar-year 2008 return.
Let your $1,000 follow that price change from the peak, with no money added or withdrawn. We leave out dividends, costs, taxes and inflation.
That leaves $432.25, about 43 cents of each starting dollar. Owning many businesses had not removed their shared exposure to a credit squeeze and falling demand.
Policy helped the system stabilize
Congress authorized the US Treasury's Troubled Asset Relief Program (TARP) in 2008. Its bank investments added capital to absorb losses. In exchange, Treasury received shares and other securities.
The Federal Reserve supplied emergency loans to meet immediate cash needs and cut rates. On December 16, 2008, it set its federal funds target range at 0%–0.25%. It also used quantitative easing, central-bank asset purchases, to lower longer-term borrowing costs.
Government spending and tax cuts supported demand through fiscal policy. These measures helped stabilize the system, but jobs took longer to recover.
The Federal Reserve's history dates the US recession from December 2007 to June 2009. The stock market, economic activity and unemployment turned at different times.
| Turning point | Date | What turned |
|---|---|---|
| S&P 500 closing low | Mar 9, 2009 | Stock prices |
| US recession trough | Jun 2009 | Economic activity |
| US jobless rate peak | Oct 2009 | 10% unemployment |
Stocks began recovering while the economy still felt unsafe. Prices reflect expectations for future profits: a less bleak outlook can lift them before jobs return. These turning points became clear only in hindsight.
If your $600 bill was due on March 9, the $432.25 would leave a $167.75 gap to cover with other cash or income. A later recovery could not pay that bill on time. Diversification spread company risk; it did not turn stocks into cash available at a fixed value.
Nor did stabilizing finance restore every shareholder's investment. Shares in a failed company could remain worthless while the index recovered. The 2020 crash begins with a different cause: a public-health emergency interrupted business revenue and sent investors searching for cash.
In short
- Pooling mortgages spread individual borrower risk but left investors exposed to a broad housing slump.
- Thin capital cushions and short-term borrowing turned mortgage losses into a funding crisis.
- Lehman's failure intensified a crisis that had already begun.
- A broad stock fund still faced the economy's shared credit and spending shock.
- Stocks turned before the economy; their recovery could not erase failed investments or move a bill's due date.