Monday, 11 of December of 2017

Economics. Explained.  

Consumer Price Index

November 15, 2017

The CPI rose 0.1% in October after having jumped 0.5% in September and 0.4% in August.  During the past year the CPI has risen 2.0%.  The year-over-year increase climbed to 2.8% in February but has backtracked in the past 8 months. .  Excluding food and energy the CPI rose 0.2% in October after having climbed 0.1% in September.  Over the past year this so-called core rate of inflation has risen 1.8%, but in the past three months this inflation rate has climbed to 2.4%.  It seems to be gradually climbing.

Food prices rose were unchanged in October after having risen 0.1% in both August and September.  Food prices have risen 1.3% in the past twelve months.

Energy prices declined 1.0% in October after having jumped 6.1% in September and 2.8% in August .  These prices are always volatile on a month-to-month basis.   Over the past year energy prices have risen 6.4%.  The recent run-up in energy prices seems to reflect strengthening GDP growth around the world which is bolstering the demand for both crude oil and gasoline.  Hence, it is unlikely that energy prices will retreat by any significant amount in the months ahead.  On the flip side, should prices remain much beyond $50 per barrel, U.S. producers was well as oil exporters around the globe will boost production which should cap the increase in prices.

Excluding the volatile food and energy components, the so-called “core” CPI rose 0.2% in October after climbing 0.1% in September.  The year-over-year increase now stands at 1.8%.  The year-over-year increase in the core CPI had risen to as high as 2.3% in January before retreating.  But a lot of this softening reflects a price war amongst telecommunications firms and thereby distorts the overall run-up.  But that exaggerated price drop appears to have run its course as phone prices rose 0.4% in both September and October.  The CPI will lose the downward  bias from this component in the months ahead.

The core CPI has also benefited from a sharp slowdown in the rate of increase of prescription drug prices.  That appears to reflect President Trump’s threat to the pharmaceutical industry that he intends to cut the prices of prescription drugs by allowing consumers to purchase such drugs overseas, and by having Medicare negotiate prices directly with the insurance companies.  That caused prescription drug prices to slow markedly late last year and in the first five months of this year.  But one wonders the extent to which price increases associated with the yearend increase in health care premiums will boost medical care prices in the months ahead.

While the CPI, both overall and the core rate, have been very well contained in the first half of this year we believe that as the year progresses the core rate of inflation will have an upward bias  because of what has been happening to both shelter prices and gradually rising labor costs which reflects the tightness in the labor market as well as rebounding prescription drugs prices and a leveling off of wireless communications services.  And now, for the first time, producer prices are beginning to rise.

Shelter costs rose 0.3% in both September and October after having jumped 0.5% in August.  In the  past year they have climbed 3.2%.  This undoubtedly reflects the shortages of both rental properties and homeowner occupied housing. Indeed, the vacancy rate for rental property is close to a 30-year low. This steady rise in the cost of shelter  will continue for some time to come and, unlike monthly blips in food or energy, it is unlikely to reverse itself any time soon.

The Fed’s preferred measure of inflation is not the CPI, but rather the personal consumption expenditures deflator, specifically the PCE deflator excluding the volatile food and energy components which is currently expanding at a 1.3% rate but is poised to head higher.  The Fed has a 2.0% inflation target.  However, going forward we have to watch out for the steady increases in shelter which, as noted above, is being pushed higher by the shortage of both rental properties and homeowner-occupied housing.   Shelter is a long-lasting problem and given its 33% weighting in the CPI it will introduce an upward bias to inflation for some time to come.  We also have to watch rising medical costs(prescription drug prices in particular) and the impact of higher wages triggered by the shortages of available workers in the labor market.

Why the difference between the CPI and the personal consumption expenditures deflator?  The CPI is a pure measure of inflation.  It measures changes in prices of a fixed basket of goods and services each month.

The personal consumption expenditures deflator is a weighted measure of inflation.  If consumers feel less wealthy in some month and decide to purchase inexpensive margarine instead of pricy butter, a weighted measure of inflation will give more weight to the lower priced good and, all other things being unchanged, will actually register a decline in that month.  Thus, what the deflator measures is a combination of both changes in prices and changes in consumer behavior.

As we see it, inflation is a measure of price change (the CPI).  It is not a mixture of price changes and changes in consumer behavior (the PCE deflator).  The core CPI currently is at 1.8%.  However, with the economy growing steadily, rents rising, and the unemployment rate falling, the core inflation rate should pick up  and rise by  2.3% in 2018.  And because the core PCE increases at a rate roughly 0.5% slower than the core CPI, the core PCE should increase  1.8% in 2018.  Both rates are beginning to trend higher.

Keep in mind that real short-term interest rates are negative.  With the funds rate today at 1.1% and the year-over-year increase in the CPI at 1.8% the “real” or inflation-adjusted funds rate is negative 0.7%.  Over the past 57 years that “real” rate has averaged about plus 1.0% which should be regarded as a “neutral” real rate.  Given a likely pickup in GDP growth this year and next and a gradual increase in the inflation rate, we regard a negative real interest rate inappropriate in today’s world.  The Fed should continue to push rates higher and gradually run off some of its longer term securities.

Stephen Slifer


Charleston, SC

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