Paul Romer on Economic Growth

Aplia founder Paul Romer was recently interviewed by Russell Roberts of George Mason University (you can find the podcast here). Some of the discussion revolved around Romer's entry on economic growth in the Concise Encyclopedia of Economics.

As Romer points out in both the interview and the encyclopedia entry, small differences in the growth rate of income per capita lead to extraordinary differences in living standards over time. A simple formula allows us to consider the growth of average income over time, where n is the number of years and the growth rate is stated in decimal form:

(Initial per Capita Income Level) x (1 + Growth Rate)ⁿ

In the interview, Romer contrasts growth rates of 2.1% and 2.6% per year. For example, if U.S. income per capita is initially $30,000 and grows at a long-term rate of 2.1% per year, then after a period of 100 years, income per person will be approximately $30,000 x (1.021)¹⁰⁰ = $240,000. How much higher would income per capita be after 100 years at a growth rate of 2.3% per year? What about 2.6%?

To achieve slightly faster income growth, an economy must be able to generate more new ideas and find applications for those ideas that result in more valuable products and services. As Romer points out, human history teaches us that economic growth springs from better ideas, not just from more output. Better ideas generate greater value per unit of input.

Discussion Questions

1. Consider the benefits of a simple idea Romer mentions in his encyclopedia article: the one-size-fits-all lid for coffee cups. How do you think this idea generated more value per unit of input for the coffee-cup manufacturer? What about the coffee shop?

2. According to Romer, "The knowledge needed to provide citizens of the poorest countries with a vastly improved standard of living already exists in the advanced countries." What types of policies serve as barriers to the flow of ideas into poor countries? What types of policies might allow poor countries to take advantage of existing ideas and, as a result, contribute more new ideas of their own?

3. Faster growth and higher living standards depend in part on the strength of the incentives we face to generate and apply new ideas. When people can benefit from an idea without paying for it, the incentive to develop new ideas will be weaker. On the other hand, once an idea is discovered, not allowing it to be shared can be inefficient or even immoral. How do intellectual property rights, such as patents and copyrights, strengthen the incentive to discover new ideas? How might intellectual property rights hinder economic growth? Congress is currently considering reforms to patent laws in the United States. (A recent PC World article highlights the difficulty of designing patent laws that give inventors an incentive to develop new ideas while at the same time encouraging the rapid diffusion of new ideas at minimal cost.)

4. What, according to Romer's piece, are meta-ideas? What meta-ideas have we used in the past to strengthen the incentives to develop new ideas?

A Failure of Markets?

As everyone learns halfway through their first principles of economics course, sometimes markets "fail." Many economists argue, however, that the so-called failure of markets is just the reverse: it's the fact that there aren't enough active markets to reach an efficient outcome.

But can there be too many markets? Consider the latest problem with the housing market. In the good old days, when you took out a loan to buy a house, you had to convince the lender that you were creditworthy. After all, if you defaulted on your loan, they would be the one holding the bag. So they had a strong incentive to make sure that you could make your monthly payments.

This isn't the way loans work anymore, thanks to a financial innovation called mortgage-backed securities. What happens is this: when a homebuyer takes out a loan from a bank, the bank bundles that loan with many other loans to create a kind of mutual fund—except that instead of containing stock from hundreds of companies, this fund includes the debts (mortgages) of thousands of homeowners. The idea is simple: as with any mutual fund, even if a single homeowner defaults, it has a negligible effect on the value of the overall fund. The fund's price should reflect the overall risk of all the homeowners rather than the particular risk of any one homeowner.

This notion illustrates the concept of diversification—the fact that although one borrower may have considerable risk, much of that risk is unique, or diversifiable. A well-diversified portfolio of mortgages is only subject to systematic, or non-diversifiable, risk, and its value should reflect that. In other words, with a new kind of security and a market for it, the capitalist system becomes more efficient, because it spreads borrowers' risk across a wide class of investors rather than concentrating it on single lenders (banks, in this case).

So what's wrong with this picture? Think back to the initial lender. They know that they're not making a long-term loan—all they're doing is making a loan that they're then going to sell in this new market. Once they've sold the loan, their exposure to the loan's risk is over. Therefore, they have little incentive to see whether a homeowner can actually afford the payments, because they no longer bear responsibility for the credit decision. Quite the reverse, in fact: they have an incentive to sell the mortgage even if the homeowner cannot afford the payments—for example, by setting a low teaser rate that starts out fixed, but then balloons into a drastically higher variable rate. This has been one root cause of the various scandals about predatory lending practices that have been in the news in the last few months.

In the meantime, those looking to buy a home with no money down might take some advice from Saturday Night Live:



Discussion Questions

1. The crisis in the financial markets has caused some people to lose their jobs and made it harder to apply for a home loan, causing home sales to decline, both of which are very upsetting to Jim Cramer. Indeed, whenever a bubble bursts, lots of people get hurt, or at least find themselves considerably worse off than they were in the artificially inflated world of the bubble. Suppose you were a policymaker overseeing a market in which people were prospering in a way that was unsustainable. What would you do?

2. Cramer practically begged the Federal Reserve to intervene, which it did by lowering the discount rate (though not, presumably, because Jim Cramer asked it to). Does this get at the root cause of the problem? If not, what would?

3. How should society decide who gets to own a home and who does not? What would be the ideal set of institutions that could help achieve the optimal solution to such a problem? Could mortgage-backed securities play an important role in your solution?

Lender of Last Resort

Rising foreclosures among homeowners with subprime mortgages led to unusually tight credit conditions in the banking system last week. Banks became reluctant to provide routine short-term loans to one another for fear that a borrowing bank's balance sheet would be too heavily concentrated in shaky subprime loans. When banks are reluctant to lend to each other, they tend to make fewer loans to businesses and households. Liquidity—the ease with which banks lend to creditworthy costumers and institutions—began to dry up. On August 17, the Fed entered the fray.

In two press releases (here and here), the Fed acknowledged that recent reluctance to lend posed a threat to economic growth, and in a rare move, it encouraged banks with limited credit access to borrow directly from the Fed by lowering the discount rate. The discount rate is the interest rate at which banks borrow from the Fed. The Fed typically sets the discount rate 100 basis points (1 percentage point) above the rate at which banks lend to one another (the federal funds rate). On August 17, the Fed narrowed the spread between the discount and federal funds rates to 50 basis points—thereby reducing the penalty associated with borrowing from the Fed.

By lowering the discount rate, the Fed was fulfilling its function as the lender of last resort. To see why the Fed stepped in, it helps to consider how subprime fears might affect the availability of loans for creditworthy borrowers. Banks, especially large ones, often borrow in order to meet the Fed's reserve requirement (the fraction of the bank's deposits that must be held in reserve rather than being lent out). Without knowledge of which big banks will be affected by subprime foreclosures, other banks that would typically lend some of their excess reserves to big banks at the federal funds rate will be reluctant to do so. If large banks that are short on required reserves find it difficult to borrow reserves in the federal funds market, they will be forced to call in loans, and they'll be hesitant to make any further loans. If banks call in loans and hesitate to lend to even creditworthy people and businesses, loan-dependent consumption and investment spending will fall, leading to slower economic growth, or worse, recession.

By reducing the discount rate, the Fed hopes to increase liquidity in financial markets by making it easier for banks to obtain short-term loans. If the policy works, creditworthy borrowers will not have any trouble obtaining loans for houses, cars, factory expansions, office buildings, and the like. As the subprime crisis subsides, regular credit conditions should prevail and the Fed will be able to return the spread between the federal funds rate and discount rate to its initial value of 100 basis points. If the credit crisis persists in spite of the discount rate move, the Fed will have to take stronger action. Read a recent Bloomberg column by John Berry to find out more.

Discussion Questions

1. In times of financial crisis, the Fed functions as a lender of last resort. More typically, the Fed's role is one of economic stabilization—maintaining low and stable inflation as well as full-employment output. How does the Fed's discount rate decision help it to fulfill its roles as lender of last resort and economic stabilizer?

2. Berry's column mentions "moral hazard" several times. In what way does the Fed's discount rate decision risk moral hazard?

3. Fears about losses from assets backed by subprime mortgages were at the root of much of the financial turmoil of recent weeks. According to Berry's column, how do the estimated losses from the default of subprime borrowers compare to the total assets of the U.S. and Euro-area banking sectors?

4. If the credit crisis continues and economic growth suffers, how might the Fed respond?

5. According to Berry, "…growth may have been damaged even if [credit] markets do settle down relatively soon." How would a temporary credit crisis damage economic growth? Consider the links between lending, housing prices, household wealth, and consumption, as well as the link between lending and investment.

Central Banks to the Rescue

World financial markets woke up to a rude surprise on the morning of Friday, August 10. The U.S. subprime mortgage debacle, which was originally thought to be well-contained within a small segment of the U.S. mortgage market, had spread to Europe. This was the straw that broke the camel's back, especially after several hedge funds from highly reputable investment companies collapsed due to heavy reliance on mortgage-backed securities. Hearing this news, bondholders and stockholders were quick to sell their risky holdings in exchange for liquidity (also known as money), which is relatively stable in value.

Aside from the fact that a sudden spike in selling activity in financial markets reduces the paper wealth of investors, it could quite possibly reduce real wealth. First, let's examine the money market effects of a sudden bond and stock sell-off due to a rise in risk aversion. For simplicity, we'll assume there are only three forms of financial assets: bonds, stocks, and money. The sell-off raises the demand for money from MD1 to MD2, as shown in the diagram below.

If the central bank does nothing and fixes the money supply at MS1, the equilibrium interest rate increases from 5.25% to 10%. The economy moves from point A to point B.

Second, let's examine the output market effects of a sudden bond and stock sell-off assuming that the central bank keeps the money supply constant. Higher interest rates mean a higher cost of borrowing for households and firms. Since big-ticket items such as automobiles, factories, and machinery are usually debt financed, consumption and investment spending (on physical capital) will decrease. Because consumption and investment spending are the two most important components of aggregate demand, a lack of central bank intervention will lead to a decline in aggregate demand from AD1 to AD2, as shown in the graph below.

If the central bank does nothing and fixes the money supply at MS1, the equilibrium interest rate increases, which reduces aggregate demand and causes a recession in the short run. The economy moves from point A to point B.

Third, let's examine how central banks around the world reacted to the liquidity hoarding. As the New York Times put it, "central banks around the world acted in unison… to calm nervous financial markets by providing an infusion of cash to the system." The Federal Reserve, along with most central banks, believes that fixing the interest rate is a better policy to maintain price stability and full employment. The Fed performed the cash infusion through of a series of government bond purchases known as open-market purchases, which is another term for the purchase of government bonds by the Fed. The cash infusion, or reserve injection, as textbooks call it, shifts the money supply curve from MS1 to MS2. The reserve injection effectively keeps the interest rate constant and avoids a recession.

If the reserve injection fails to calm financial markets and investors continue to hoard liquidity while selling bonds and stocks, central banks could inject additional reserves into the banking system through additional open-market purchases. The amount of money the Fed can create through purchasing government bonds is nearly limitless.

Read the Federal Reserve's actual press release from Friday, August 10, 2007.

Discussion Questions

1. For the most part, the Federal Reserve's main concern is first and foremost inflation, and secondarily unemployment. Given these two goals, should the Federal Reserve intervene every time the stock market takes a plunge?

2. Most economists believe that a permanent increase in the money supply will generate inflation and make the prices of everyday goods and services higher than they are today. Is this scenario likely given the large reserve injections in the U.S. and world money markets? Why or why not?

3. Some economists believe that markets are highly efficient in the sense that prices and interest rates adjust immediately to guarantee full employment. If this were true, would the Fed's reserve injections have any effect on credit markets or the economy as a whole?