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Yes, The Right Wing Lies When They Say Obama is a Profligate Spender

Part III – How to think about time series data.

For reference:
Part II  Federal Spending as a Fraction of GDP

Part I  Federal Spending Growth

Some commentors to the previous posts have rightly concluded that I consider spending under Obama in the context of historical trends.  In fact, if you don’t consider historical trends, you are ignoring the most important element of context that is available.  I only mentioned trends briefly in Part II, but the directional changes in the graphs of Parts I and II implicitly suggest them.

Time series data that relate to the size of the population, the government, or the economy generally follow a quasi-exponential growth pattern.  I say quasi- because a perfect exponential growth pattern  results from a continuous constant rate of growth, while real world growth rates vary from year.  Graph 3 of Part II shows how these variations have occurred over several decades.  Usually this does not result in a large or permanent deformation in the shape of a quasi-exponential curve, since the growth rate typically oscillates irregularly around a mean value that only changes slowly over time.

Graph 2 in Part II shows that the spending and GDP growth curves stay close to exponential tracks over long time spans.  It also illustrates that the recent recession was one of those rare times when growth rates deviated substantially.

Human eye-brain coordination doesn’t deal well with exponential curve shapes.  Straight lines are much easier to comprehend and extrapolate.  Graphing quasi-exponential data on a log scale reduces the curve to a quasi-straight line that is much easier to use and understand.

Graph 1 shows Federal Spending and GDP, since 1995, plotted on a log scale.  Constant growth results in a straight line segment, and a higher growth rate causes a steeper slope.  Zero growth shows up as a horizontal line.   I’ve again included a line for 5 times spending, to get a close overlay with the GDP line.

 Graph 1.  Spending and GDP since 1995 (log scale)

There is an upward bend in the spending line in 2000.  This is most easily seen in the blue line.  During the 90’s, we can see that GDP grew faster than spending.  In 2001-2, GDP growth flat-lined, as expected during a recession. Then, from 20002 to 2008, the growth rates for GDP and spending were close to identical.  Both lines twist during the most recent recession.  Curiously, spending growth was flat for a large portion of 2008.

Since the recession, the spending lines are very close to flat, and GDP growth has been anemic.  Here is a close up.

Graph 2.  Spending and GDP since 2007 (log scale)

Graph 3 provides context, all the way back to 1947.  Ponder the inflection points and slope changes at your leisure.

Graph 2.  Spending and GDP since 1947 (log scale)

Note that there are only two flat-ish spots in the spending lines: now, and during the Eisenhower administration. The current administration has, at least temporarily, broken the decades-long trend in continuous spending increases. 

To emphasize the obvious, spending growth is now very close to zero.  In context, this is remarkable.  Saying Obama is a profligate spender is a lie. 

In this post, I am not suggesting that the rate of spending growth under any president is good, bad, appropriate or inappropriate.  I am only pointing out what was and is. 

So, this is how you think about time series data.
0) Forget your preconceived notions.    (Frex:I had no idea that spending growth has essentially stopped until I looked at the data.)
1) Identify trends. The history of time series data provides meaningful context.
2) Identify break points and trend changes.  These are key data points.
3) Note the directions of these changes.
4) Think hard about what these observations are actually telling you, not what you want them to say.
5) Double down on 4) if you are looking at a ratio.  Ponder that denominator.
6) Don’t cherry pick.  It’s dishonest.

There are a lot of ways to look at a data set: linear and log scales, rate of change, etc.  Chose the one that gives the clearest picture of the data you want to analyze, or simplifies the analysis, or makes it easier to understand.  Studying different views can be informative, as can a comparison of different data sets. 

Here is the working page at FRED for the graphs in this post.  I encourage the interested reader to spend some time working with the capabilities of this very powerful tool.

Editorial Comment:
In case it’s not obvious, I’ll tell you that I write these posts because they interest me and I think they generate some knowledge, or at least information, that is worth sharing.  I have virtually no interest in the fool’s errand of convincing anybody that I am right – either the data analysis convinces you or it doesn’t.  So unless you have better data, or can point out some specific flaw in my reasoning [and then tell me specifically and in detail how to get it right] don’t bother arguing with me.

I appreciate rational discourse, and am always willing to engage thoughtful readers. I’m also willing to be proven wrong by a cogent argument.  That said, though, I don’t really care if anyone comments.  At this point, I’d almost rather nobody did.  But if you chose to, please do me the courtesy of having your comment be somewhere in the general vicinity of on-topic.  And – fair warning: naked assertions and unsubstantiated ideologically approved talking points will be scoffed at, so please check that nonsense at the door.

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Why Spending/GDP is a Terrible, Horrible, No Good, Very Bad Metric For Judging Obama’s Performance

A post like this really shouldn’t be necessary, but part of the right wing canard that Obama has been a profligate spender is based on spending as a percentage of GDP.

It looks like this – Graph 1.

Graph 1.  Fed Expenditures/GDP

Sure enough, by the end of Clinton’s term the ratio had fallen from Reagan’s high of 24% to a modern low of 19%.  But note that the 19% value wasn’t typical.  It was the end point of a decade-long decline.  And, yep, there’s Obama with an all-time-high approaching 26%.

What otherwise intelligent, and sometimes even famous people seem to ignore though, is that every ratio has not only a numerator but also that ol’ devil denominator.   Let’s have a look at both of them.  Graph 2 shows GDP and Expenditures since 1980, expressed in $ Billions.  I’ve also added a line representing 5* Expenditures, since 20% of GDP is a reasonable rough estimate for the post WW II era.

Graph 2.  Expenditures and GDP Compared

Actually, the 5x Expenditures line runs pretty consistently above the GDP line, telling us two things that we should have already known from looking at Graph 1.  First, Expenditures greater than 20% of GDP have been the norm since before 1980, and 2) Clinton’s final number is not representative of anything other than a single year.  Using it as a comparator is cherry-picking and fundamentally dishonest.

The 5x line also emphasizes that the majority of the spending increase under Obama unavoidably occurred during the officially designated recession.  The GDP line shows that, post recession, GDP growth has not recovered to the pre-recession trend line.  In fact, growth has established a new trend line with a lower slope.  This is unprecedented in the scope of FRED historical data.  My guess is that insufficient Federal spending has been a big drag on this recovery.  But it’s also true that GDP growth has been in secular decline since the Reagan administration.  Note that skewing the denominator down will automatically skew the ratio up.  This is what Bill Clinton calls “arithmetic.”

Slicing across this a different way, Graph 3 gives us year-over-year percentage growth in Expenditures and GDP, dating back to the Eisenhower administration.

Graph 3.  YoY % Change in Expenditures and GDP

A few simple observations:
– The spending increase during the recent recession was modest by any standard, and dwarfed by earlier surges.
– That increase, coupled with the most severe GDP decline since the other Great Depression gave our beloved ratio a terrible, horrible, no good, very bad double whammy.
– GDP growth during this recovery is only marginally better than it was during the 2001-2 low, and far below Clinton era levels.
– Clinton was the most consistently frugal president of the post WW II era – until now.
– Since the recession was declared over, B. Hoover Obama has been miserly.

One can legitimately argue that Obama’s approach to the economy has been excessively conservative.  Krugman has made this point repeatedly.  I often say that Clinton governed to the right of Eisenhower – who was a genuine deficit hawk – and that Obama is to the right of Clinton. That is intended to be slightly hyperbolic, but using this data as the benchmark, it’s dead on.

Any questions?

Cross posted at Retirement Blues

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Jonathon Portes on Macroeconomics and the deficit

Jonathon Portes on macroeconomics and the deficit:

As we all know, since then both the US and UK have had deficits running at historically extremely high levels, and long-term interest rates at historic lows: as Krugman has repeatedly pointed out, the (IS-LM) textbook has been spot on.  Empirically (and theoretically) well-founded? Definitely.  As Simon Wren-Lewis points out here. Recent developments have in many ways been a vindication of the basic Keynesian model that lies at the heart of any undergraduate macro course.

The policy implications are of course not unambiguous – the conclusion isn’t “borrow as much as possible” – but the implication that, when you have excess (desired) private saving, government borrowing won’t push up long-term interest rates is obviously important. So score one for macro 101. Of course, there were economists, not just people like Ferguson, arguing the contrary in public; but generally not on the basis of a different analytical framework, with the result that their analysis was confused at best. See for example my debate with David Smith here, where David begins by explaining that low interest rates reflect “market confidence”, and ends up by saying that they reflect the “fragility of the banking system.”

Of course, some countries – all, not coincidentally, members of the eurozone – that have high deficits have indeed seen interest rates soar. So a second, and equally policy-relevant, example is “what drives the possibility of a sovereign debt crisis?”.  Here the economic theory was set out very clearly by Paul De Grauwe, of the University of Leeuwen, for example here (and versions of this paper were circulating as far back as mid-2010):

This separation of decisions [in a monetary union] – debt issuance on the one hand and monetary control on the other – creates a critical vulnerability; a loss of market confidence can unleash a self-fulfilling spiral that drives the country into default.  Suppose that investors begin to fear a default by, say, Spain. They sell Spanish government bonds and this raises the interest rate. If this goes far enough, the Spanish government will experience a liquidity crisis, i.e. it cannot obtain funds to roll over its debt at reasonable interest rates…

It doesn’t work like this for countries capable of issuing debt in their own currency. To see this, re-run the Spanish example for the UK. If investors began to fear that the UK government might default on its debt, they would sell their UK government bonds and this would drive up the interest rate. After selling these bonds, these investors would have pounds that most probably they would want to get rid of by selling them in the foreign-exchange market. The price of the pound would drop until somebody else would be willing to buy these pounds. The effect of this mechanism is that the pounds would remain bottled up in the UK money market to be invested in UK assets.

The economic theory underlying this verbal explanation is clear and convincing. And so is the empirical evidence.  Not only have Japan, the US and the UK all failed to experience self-fulfilling liquidity crises resulting from their very large deficits, so has every other developed country that issues debt in its own currency. 

This contrasts, of course, with the eurozone experience; and it is precisely what theory predicts. It is quite rare that an economic theory – macroeconomic or microeconomic – is so clearly and comprehensively vindicated so quickly. Again, the policy implications are not that we (or the US) can or should expand our fiscal deficit without limit. But they are very clear that we should ignore the ratings agencies,  and that anybody who is still arguing that the current path of fiscal consolidation – and the economic damage it has done – was necessary to preserve “market confidence” has chosen to ignore the evidence. 

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