# It’s done “for ease of comparison,” the government says.

Note from dshort: I’ve updated the last chart in this commentary to include today’s Q4 GDP Advance Estimate of real quarterly GDP. The BEA’s annualized growth rate of 2.6% (2.64% to two decimals) is based on a 0.65% quarter-over quarter percentage change.

Pop Quiz! You just received your quarterly statement from the company that manages your 401(k). Which result would you prefer?

A) Your portfolio is up 1.22% for the quarter.
B) Your portfolio is up 4.97%* for the quarter.

Well, that’s certainly a no-brainer question. You’d definitely choose option B.

However, buried in the fine print of the document for option B is the footnote for that little asterisk:

*Compounded Annual Percent Change

So this was a trick quiz question! The two answers are identical. To two decimal places, the quarter-over-quarter gain of 1.22% becomes 4.97% if we state it as the compounded annual percent change.

Of course, in the real world, no investment company would issue a 401(k), IRA or any other account statement reporting your quarterly returns at a compounded annual rate.

But that’s exactly the way the US Department of Commerce, via the Bureau of Economic Analysis, reports quarterly GDP. Here is the opening of the December 23, 2014 report for Third Quarter GDP:

Real gross domestic product – the value of the production of goods and services in the United States, adjusted for price changes – increased at an annual rate of 5.0 percent in the third quarter of 2014….

The 5.0 percent was actually 4.97% (answer B in our quiz question) rounded to one decimal. The quarter-over-quarter change was 1.22% (answer A).

Here’s a snapshot of real quarterly GDP over the past 25 years.

Here is a column chart showing the BEA’s preferred annualized representation.

Here is the same data with the more intuitive quarter-over-quarter percent change. Note that I’ve kept the same vertical axis as the chart above to illustrate the rather stunning difference between the two.

Here’s an even better way to illustrate the difference with a side-by-side comparison.

Why does the BEA calculate GDP by compounding the quarterly percent change at annual rates? They do it “For ease of comparison”. They explain their rationale here. In a nutshell, it’s a technique that’s supposed to help you compare the latest quarterly growth with the previous annual growth.

My personal view is that quarterly real GDP should be stated as the percent change from the previous quarter, the way most countries around the world represent their GDP. My suspicion is that the key driver for using the compounded data is the preference for bigger numbers: “Quarterly GDP was up 5 percent!” instead of “Quarterly GDP was up 1.2%”.

Consider this: Since the inception of quarterly GDP in 1947, the real quarterly number has been positive 84.9 percent of the time (270 quarters, 229 of which were positive and 41 negative). So the upside advantage of what amounts to “psychological inflation” of economic growth substantially outweighs the downside risk of increased psychological deflation from compounding the negative numbers.

Commerce thrives on optimism, and the inherent instinct is captured in the immortal words of Johnny Mercer’s Ac-Cent-Tchu-Ate the Positive:

You’ve got to accentuate the positive
Eliminate the negative
Latch on to the affirmative
Don’t mess with Mister In-Between.

Keep Johnny Mercer’s lyrics in mind when you read GDP reports from the Bureau of Economic Analysis. By Doug Short, Advisor Perspectives

Homeownership has plunged the fastest ever and hit a 20-year low. But Wall Street has an answer: Instead of a home, let them buy toxic, rent-based, synthetic structured securities. Read…  The American Dream Dissipates at Record Pace

## 3 comments for “Government Mind Games: Psychological Inflation of U.S. GDP”

1. Robert
Jan 30, 2015 at 7:15 pm

It is worth noting that every single dollar of deficit spending counts as a dollar of GDP “growth” and this is why we observe an endless stream of positive GDP growth numbers. In the past, recession was defined as two or more consecutive quarters of decreasing GDP, but although one speaks, for example of the “Great Recession” of 2007-2009, there was no decline in nominal GDP. Factoring in inflation- not the official inflation that ignores food, fuel and clothing- it is another matter

• mick
Jan 31, 2015 at 12:04 am

That’s right, I had forgotten all about that. The US economy is nothing but one big fraud based on debt.

2. Fred_Flintstone
Feb 1, 2015 at 7:43 am

Ah, facts. Gets them every time. So, if you overstate GDP (by changing the way it is calculated, etc) and understate inflation (through calculations, hedonics, etc) then you get a thriving economy….

But to the masses that are suffering a lower and lower standard of living, the real truth is obvious. Eventually, this group will see the truth and it will be large enough that something really bad happens. If we would just own up to the facts then the problems could be addressed before lots of more suffering occurs.