Visualized: US Currency in circulation, past and present

This phenomenon has been in the news recently, so I've updated this article that I originally published in 2017. The paper currency in circulation in the US is mostly $100 bills. And not just by a little bit -- these account for 34% of the notes by denomination and nearly 82% of the value (data as of 2022).

I originally wrote this article when I was inspired by a news story on NPR's Morning Edition about the merits and risks of the $100 bill. There are a lot of them in circulation, but no one knows exactly where they are. According to the report, they are seldom used for legitimate business transactions. When a transaction reaches into the hundreds of dollars, the business parties tend to resort to a digital transaction (or maybe a good-old-fashioned personal check). Large cash transactions are often used to avoid taxation or, more nefariously, to hide criminal activity.

It was easy to find the data on the US Federal Reserve: Currency in Circulation web site. I could have copied and pasted the table for use in SAS, but the Fed already makes an ASCII version of the table available for nerds like me. With a bit of SAS code I was able to download the data (using PROC HTTP), transpose it for analysis, calculate the currency values for the counts of the various notes, and create a graph that verifies what I heard on the news. Indeed, much of our nation's cash wealth is floating around on a bunch of Benjamins.

The percentage of wealth represented in the $100 bill has grown over the past 20 years, perhaps at the expense of the far-more-ATM-friendly $20 bill. In 1996, the ratio of hundreds-to-twenties (in cash value) was 61/20. In 2016, it was 79/12. The following table shows the two years side-by-side. $100 bills increased by nearly 18 percentage points, while all other notes decreased. $20 notes were the biggest loser at -8.3 points, and $50 notes were next at -5.8 percentage points.

If we look at the percent breakdown by bill counts (instead of value), you can see the shifts a bit differently.

I created those two plots by calculating the percentages with PROC FREQ, and then using PROC SGPLOT to graph Year, using the percentages as the response value and stacking the data by Denomination. I used GROUPORDER=Data to keep the data colors and legend consistent across the different graphs. The raw values are interesting to examine as well, as it more clearly shows the trends for the past 20 years. Here are the two representations (cash value and bill counts) with their actual values and not just the percentages.

An interesting aside: the $2 bill remains a novelty. I had the opportunity to spend a few of these recently, and the person receiving them had to be convinced that they were real money. It made me want to secure more $2 bills (a.k.a. "some Jeffersons") for future transactions -- that's the sort of trouble-making consumer that I like to be.

In case you're interested, here's the SAS program that I used -- try it yourself! This should work fine in any recent SAS version, including in SAS OnDemand for Academics.