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Debt Made Beautiful

debtDoes the prospect of a looming U.S. government shutdown depress you?

Are you tired of the ongoing game of Chicken played over our federal budget? The dissonant hysterics of deficit drama queens? The glib arrogance of deficit deniers?

Then it might be a good time to take a break and focus on something more pleasant. Something you can control. Something you can improve and make more beautiful.

Like editing your graphs in Minitab.

In this post, I'll show you how to gussy up a graph with a few simple maneuvers.

(If you want to follow along and you don’t have Minitab, download a free trial copy.)

1. Display the Graph

First, open this data set in Minitab. Choose Graph > Time Series Plot > Simple. In Series, enter ‘% GDP’. Click Time/Scale. Select Stamp and enter Year as the Stamp column.

After you click OK, you should see the graph below:

original graph

The graph shows the annual deficit or surplus of the U.S. federal government each year from 1929 to 2012, represented as the percentage of the gross domestic product (GDP). Notice the valleys, peaks, and trends in our modern deficit history.

2. Change the Title

Let’s make the main title of the graph more accurate and descriptive. Double-click the title to display the Edit Title dialog box. Under Text, enter Annual U.S. Deficit/Surplus. Note you can also reformat many other attributes of the title. You can also reformat the labels for the X and Y  scales. 

3. Add a Reference Line

To more clearly see when the U.S. government ran a surplus or a deficit, add a reference line at the value of 0 on the vertical (Y) scale. Right-click the graph and choose Add > Reference Lines. In Show reference lines at Y values, enter 0.

After you click OK, the reference line at y = 0 appears. If you want to edit the reference line, just double-click it. I’m leaving mine with the default format:

reference line

4. Change Symbols for Data Points

To more clearly differentiate surpluses from deficits, change the surplus data values to black triangles.

Click on a data point that represents a surplus (above the reference line). All the data points will be selected. Click the data point again to select only that point. Then double-click the selected point to show the the Edit symbols dialog box.

From Symbols, choose Custom. Change Type to triangle and Color to black. After reformatting the surplus data points, the graph looks like this:
 
symbols

Now you can clearly see that in most years, the U.S. federal government has operated in the red.

5. Annotate the Graph

Graph annotation tools allow you to add a variety of lines, shapes, text and other features to the graph. The tools, located on the annotation toolbar shown at the bottom right, are simple but surprisingly versatile.

annotation toolbar

For example, you could add transparent ellipses to the graph to show economic recessions. (For the examples below, the data used for the annotations are recorded in the Minitab ReportPad).

recession

Fourteen ellipses for the 14 official U.S. recessions since 1929. More than I thought!

Note that each recession is characterized by a sharp fall in the connect line. That makes sense, because typically in a recession the economy (GDP) shrinks and government revenue falls, causing a sharp increase in the federal deficit.

One notable exception is the brief recession of 1945 (the skinny ellipse). This is the only recession in modern times where the deficit (in %GDP) actually dropped—right after the end of WW II. I’ll let you ponder that anomaly.

Add line segments and text labels

Personally, I don’t think any U.S president is a master of the country’s economy. But they take the blame (or the credit) from the U.S electorate, so let's add vertical line segments and text labels to show the tenure of each presidential administration.

administrations

Quite a few of the ellipses fall on or adjacent to the dotted lines defining the terms of different presidents. That's very fortunate, as it enables a president to generously give credit for a recession to their predecessor or successor.

Editor > Duplicate Graph Has Got Your Back

I wonder. Would it be easier to see the deficit trend for each administration if the recession ellipses were removed from the graph? But those ellipses took time to position correctly, so I'm hesitant to remove them.

Luckily, there's a convenient command that allows you experiment with formatting without worrying about  losing your previous work. Select the graph and choose Editor > Duplicate Graph. Now you have a copy of the graph, including all the annotations and editing you've added, to freely experiment with. The previous graph is still there as a backup in case you change your mind.

Without the ellipses, the deficit trends during each administration are easier to see:

no ellipse

That's better.

Now, how about about adding line segments to show the average deficits over each president's entire tenure in office?

To position annotated line segments precisely, first add a reference line at the exact Y value for the average deficit (see step 3). Using the reference line as a guide, position the annotated line segment. Then delete the reference line.

For visual clarity, I also removed the individual data symbols in the graph.

Note: The average deficit over the complete tenure of the Obama administration can't be determined until his second term is complete. Predicting what that average is going to be is, in essence, a big part of the current congressional budget debate. If you want to add the line based only on his first term, it falls at -8.38.

final

Now that the graph is edited and annotated, it’s time to interpret it.

So. Who's done a better job of managing federal deficits in modern history -- the blue team or the red team?

I'll let you decide.

If you can't make up your mind by midnight tonight, no worries. Your Minitab project will not shut down.

 

Data Source: Federal Reserve Bank St. Louis. Economic Data. Federal Surplus or Deficit as a Percent of Gross Domestic Product. Available at: http://research.stlouisfed.org/fred2/series/FYFSGDA188S/downloaddata?cid=5

 

Additional information

This post just covers the tip of the iceberg of the graph editing features in Minitab.  To learn more, see Minitab Help.

  1. In Minitab, choose Help > Help.
  2. Click the Contents tab.
  3. Expand the Graphs book.
  4. Expand the Graph Editing Tools book. (The Overview is a good place to start. )

graph editing

To follow the developments in the current U.S. federal government funding debate in Congress, without the hoopla, see http://www.c-span.org/

Comments

Name: Tom • Monday, September 30, 2013

Wonderful article. How do you add vertical line segments?


Name: Patrick • Monday, September 30, 2013

Thanks much for your feedback Tom.

Your comment made me realize I'd forgotten to show the Minitab graph annotation toolbar when the post first went live. I went back and added an image of the annotation toolbar in Step 5. If the toolbar does not appear when you are using Minitab, choose Tools > Toolbars > Graph Annotation Tools. The button for adding line segments is the 5th button from the left on the annotation toolbar. Thanks again!


Name: Tom • Monday, September 30, 2013

Also, I found that rather than individually formatting data points, you can assign formatting by a grouping variable. So if you have another column identifying surplus and deficits, you can quickly format an entire group.
Edit Symbols > Groups Tab > Categorical Variables for Grouping


Name: Patrick • Monday, September 30, 2013

Excellent point!

And if you want to create that column that identifies surpluses vs deficits quickly (rather than do it by hand), you can use the Minitab Calculator.

Choose Calc>Calculator. In Store results in variable enter the column number of a blank column (c3). Suppose data values of the surpluses/deficits are in column c1. In Expression, enter "IF(C1> 0, "surplus","deficit"). Presto! Now you've got the column for the grouping variable so you can format all the surplus data points in one easy maneuver, as you suggested.


Name: tamoghna • Tuesday, March 25, 2014

It was fun to follow along this engrossing project. I found holding the 'shift' key while drawing the vertical line makes them perfectly straight.


Name: Patrick • Tuesday, March 25, 2014

Great tip! I didn't know that myself!


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