Tuesday, February 11, 2014


If you go to a FRED page like Federal Government Current Receipts (FGRECPT) you get a graph and some other stuff. If, instead of editing the graph, you look over at the sidebar, one of the items under Tools is "Vintage Series in ALFRED". If you click that from FRED's FGRECPT page, you get the ALFRED page for FGRECPT. Then you can edit it just the same as at FRED, except you can also select new or old versions of the data. New or old "vintages" they call them.

You can compare new and old vintages. For example, here are eight views of Federal government current receipts in the 1960s -- the the one that was current when I made the graph, and the first vintage from each of the previous seven years:

Graph #1
They all follow the same path.

Here now are the first vintages for the most recent eight years, for Federal government current expenditures in the 1960s:

Graph #2
There are two lines visible. Sometime since 2007 there was a change in the FGEXPND data. But when? How many lines are hidden beneath the higher line? How many beneath the lower? I switched the setting to make it a bar graph so I could see the separate vintages. But ten years of data was too much. The details were too small to see. So I reduced it to just one year, just 1960:

Graph #3
One vintage from each of the last eight years. Only the most recent one shows a significant difference. Quite a weird coincidence that I waited until now to investigate Mike Kimel's data.

Graph #3 looks at the first vintage for each year. Graph #4 looks at every month's vintage. So, the ten most recent vintages. That takes us back before the "comprehensive revision" of mid-2013:

Graph #4: The Change First Appears in the July 2013 Vintage

I should have known.

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