here is widespread consensus that the conventional and unconventional monetary policies that world’s major central banks implemented in response to the global financial crisis prevented a deeper recession and higher unemployment than there otherwise would have been. These measures, along with a lack of demand for credit as a result of the recession, contributed to a decline in real and nominal interest rates to ultra-low levels that have been sustained over the past five years.

A new report from the McKinsey Global Institute examines the distributional effects of these ultra-low rates. It finds that there have been significant effects on different sectors in the economy in terms of income interest and expense. From 2007 to 2012, governments in the eurozone, the United Kingdom, and the United States collectively benefited by $1.6 trillion both through reduced debt-service costs and increased profits remitted from central banks (exhibit). Nonfinancial corporations—large borrowers such as governments—benefited by $710 billion as the interest rates on debt fell. Although ultra-low interest rates boosted corporate profits in the United Kingdom and the United States by 5 percent in 2012, this has not translated into higher investment, possibly as a result of uncertainty about the strength of the economic recovery, as well as tighter lending standards. Meanwhile, households in these countries together lost $630 billion in net interest income, although the impact varies across groups. Younger households that are net borrowers have benefited, while older households with significant interest-bearing assets have lost income.

 

Ultra-low interest rates have had distributional effects on interest income and expenses.

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The impact that ultra-low interest rates have had on banks has been mixed. They have eroded the profitability of eurozone banks, resulting in a cumulative loss of net interest income of $230 billion between 2007 and 2012. But banks in the United States experienced an increase in effective net interest margins and a cumulative increase in net interest income of $150 billion. The experience of UK banks falls between these two extremes.

Life-insurance companies, particularly in several European countries, are being squeezed by ultra-low interest rates, so much so that if this environment were to continue many of these insurers would find their survival threatened.

Theoretically, ultra-low interest rates may have resulted in higher asset prices, and this effect may have offset lost interest income for households and other investors. But we find a mixed picture.

Rising bond prices are the flip side of declining yields, and the value of sovereign and corporate bonds in the eurozone, the United Kingdom, and the United States increased by $16 trillion between 2007 and 2012. Investors that mark the value of their assets to market have therefore seen a significant gain on their fixed income investments, at least on paper.

Ultra-low interest rates are likely to have bolstered housing prices by lowering the cost of mortgage credit. This effect is most clearly seen in the United Kingdom, where the majority of mortgages have variable interest rates that have automatically adjusted downward. The impact is less clear in the United States, where the recovery in housing prices has been dampened by an oversupply of housing, high levels of foreclosures, a predominance of fixed-rate mortgages, tightened credit standards, and the prevalence of homes with negative equity whose mortgages cannot be refinanced.

We found little evidence that ultra-low interest rates have boosted equity markets. We cannot discern a large-scale shift into equities as part of a search for yield by investors, and price-earnings ratios and price-book ratios in stock markets are no higher than long-term averages. Although stock prices do react to announcements by central banks, these are transitory effects that do not persist.

If one accepts that housing prices and bond prices are higher today than they otherwise would have been as a result of ultra-low interest rates, then the increase in household wealth and the possible additional consumption it has enabled would far outweigh the income lost to households. But we are skeptical about whether increases in wealth have translated into higher consumption in today’s environment, given that housing prices in the United States remain far below their peak. Moreover, it is more difficult for today’s households to borrow against any increase in wealth because of tighter credit standards.

Ultra-low interest rates do appear to have prompted additional capital flows to emerging markets, particularly into their bond markets. Purchases of emerging-market bonds by foreign investors totaled just $92 billion in 2007 but had jumped to $264 billion in 2012. Emerging markets that have a high share of foreign ownership of their bonds and large current account deficits will be most vulnerable to capital outflows if and when central banks begin tapering current policies.

There are likely to be risks ahead whether asset purchases are tapered and interest rates rise or, alternatively, if current monetary policies continue and interest rates remain low. In the first scenario, the benefits gained or losses incurred could be reversed. Government interest payments on debt, for instance, could rise up to 20 percent. Amid anecdotal evidence that some investors have increased their leverage to amplify returns in some markets, rising interest rates could lead to a collapse in leveraged trades and could pose a threat to some financial institutions. Capital flows to emerging markets could reverse. Investors in bond markets forced by accounting rules to mark to market could face large write-downs. Eurozone countries could be caught in a crosswind if rates increase in the United States before they do in Europe, leading to a shift in foreign capital from Europe to the United States. In the second scenario, life insurers and banks in Europe would experience continued erosion in their profitability. A continuation in ultra-low interest rates could also prompt higher leverage and the return of asset-price bubbles in some sectors, especially real estate.

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