The US is finally putting a woman on the $20 bill — but 48 other countries beat us to it

Yesterday afternoon, the US Treasury announced that (who escaped slavery and became an abolitionist) will replace (who reputedly owned 300 slaves) on the front of the $20 bill.

Some would call that sweet justice, but the decision to include a woman on our paper currency is long overdue, especially when compared to other countries.

We spent the past week compiling data on the world's 180 recognized currencies, with several questions in mind: How many countries' currencies feature at least one woman? What percentage of the world's money pictures a woman? And which women are the most well-represented?

In a strange twist, our journey led us into the arms of Queen Elizabeth II.

The search for minted women

Using the Standard Catalogue of World Paper Money and a number of extensive bank note archives, we combed through every denomination of paper currency in the world that we could find.

For our analysis, we decided to only include currency that is currently in circulation. Short-lived commemorative bills were omitted, as were fictional characters and unidentified women (statues, angels, etc.). We wanted to hone in on real women who were honored for their achievements.

Our search yielded a sad truth: Only 48 of 196 countries feature a woman on one of their bills. That's less than one-third of the world.

Australia leads the way for gender equality on currency: Women are featured on four of its five bank notes. When an Australian blog asked the Reserve Bank why it chose to include more women, a spokesperson simply that "the bank felt it appropriate women were properly represented."

But the bigger picture is pretty bleak. Counting all denominations, the 48 countries above circulate a total of 118 bills that feature 44 women. Worldwide, there are roughly 1,300 bills total — the majority of which picture historical male figures.

This means that women are only on 9 percent of the world's paper currency. The majority of the other 91 percent depict men — though at least fifteen countries don't feature people on their currency at all.

Now let's take a closer look at the 44 women who make the cut.

In the sortable chart below, we've included each and every woman who is on a bank note, along with the country of issue, the denomination(s) she appears on, and a bit about her qualifications. Additionally, we've highlighted rows where the same woman appears on currencies in multiple countries.

A few interesting things stick out here.

For one, five of these 44 women are opera singers: Nellie Melba (Australia), Emmy Destinn (Czech Republic), Jenny Lind and Birgit Nilsson (Sweden), and Sigrid Undset (Norway).

In general, it seems that women of creative endeavors are highly valued in certain countries. Ten writers and poets (including two Nobel Prize winners) and four artists grace this list.

But there's something much bigger going on: Queen Elizabeth II is a consummate currency badass.

Elizabeth II, who turned 90 years old today, is on an insane number of bank notes. Of the 118 female-fronted bills discussed above, 74 bear her likeness. She appears on bank notes in at least 19 different countries spanning across the globe. In some currencies, her face is plastered on every single bill, from the $5 to the $100.

In this sense, she absolutely destroys any man who graces legal tender. But how did she get there?

Queen Elizabeth II crushes the currency game

As ruler of the UK, Canada, Australia, New Zealand, 12 independent nations, and several other Crown dependencies, Elizabeth II is one of the most internationally significant monarchs in history. She's served as queen through 12 prime ministers and 12 US presidents. She's not only Britain's longest-reigning monarch, but the world's longest-reigning queen.

And to add one more title to her majesty's dominance, she is also history's most prolific face on currency.

Elizabeth II began appearing on currency long before she assumed the throne: In 1935, at the seasoned age of eight, she on the Canadian $20 bill. Sixteen years later, at age 24, her portrait was used on the Canadian $2 bill.

Newly christened as queen in 1952, Elizabeth II became the default on a smattering of currencies in countries under Great Britain's rule. But it wasn't until 1960 that Britain unveiled its first Queen Elizabeth bill — a £1 bank note.

A Canadian bank note from 1935 bears the image of Queen Elizabeth — who was then 8 years old.

Though monarchs had intermittently made appearances on British bank notes in the early 20th century, it wasn't until 1960 — with Queen Elizabeth II's rise — that they became the de-facto face of the country's currency.

According to British currency expert John Keyworth, several key happenings led to the queen appearing on so many bills.

"Firstly, the Bank had been nationalized in 1946, and by portraying the monarch on its notes, the institution recognized that it was now publicly owned," he said, in an interview with the Daily Express. "And secondly, the highly specialized art of the hand-engraved portrait added a formidable anti-forgery feature."

Today, the Elizabeth II's portrait is disseminated on so many denominations of currency (74, to be precise), that Keyworth figures it is "the most reproduced image in the history of the world."

While women face a grave disparity in how frequently they're pictured on currency, Elizabeth II is a beacon of light.

Unfortunately, that light will one day fade — and when it does, Prince Charles is likely to take her place. This transition will come at a great financial cost to the UK. New currency will be designed, printed, and minted, and efforts will be undertaken to gradually phase out the queen's bills, until they are relics of the past.

Omitting the queen, only 3 percent of the world's bills feature a woman.

So, here's a call to action for the 148 countries that don't currently have a woman on their currency: Quit being a royal pain, and pull your weight.