Spreadsheet “bugs” are a problem for most data-crunching people. But most of them are not world-renowned Harvard economists using their Excel models to justify highly partisan theories. That’s exactly what Carmen Reinhart and Kenneth Rogoff were doing though. They released a paper that spawned a global movement to reduce national federal debt, only to realize their fundamental conclusions were based on a serious Excel blunder. In essence, they accidentally “hid” five rows in their Excel spreadsheet that contained GDP data from 5 of the 19 nations in their study. Reinhart and Rogoff’s key claim was that when countries reached a gross government debt equal to 90% of their GDP they hit a tipping point which caused annual economic growth to start decreasing every year. The Reinhart-Rogoff paper was music to the ears of “deficit hawks” around the world. It seemed to provide solid proof that national debt could reverse a nation’s growth. Except not. When Reinhart and Rogoff included the missing rows of data, the growth in countries with high government debt jumped to an extremely healthy +2.2% per year. D’oh! The data error was discovered by a graduate student at UMass Amherst whose econ professor had asked students to find a published paper and replicate it. When Herndon couldn’t replicate the same results, he went to his professor, who also failed to replicate the results. So they gathered a team at UMass to assemble a corrected version of the Reinhart-Rogoff paper, and then published it. Reinhart and Rogoff almost immediately responded, admitting the data error. But it was too late. The original Reinhart-Rogoff paper had already been used to support the 2013 US budget created by the Republican majority in the House of Representatives. The study had also already been used by the European Commission to justify major fiscal cuts and “austerity” measures. And Rogoff himself had already gone before a large panel of bipartisan economists warning of catastrophic consequences for the US economy, since it was in a 90% debt situation. Next time they could save time by just using Excel’s “goal seek” feature.

Microsoft Excel is one of the most powerful programs on the planet. It can generate complex financial models, run statistical simulations, and graph just about anything. But Tatsuo Horiuchi, a Japanese artist, uses Excel to make art. Using just the AutoShapes function, Horiuchi creates stunning landscapes and portraits that appear to be painted on a canvas. Horiuchi claims he just stumbled upon this new medium as a matter of frugality—he tells reporters he only started using Excel because it was preinstalled on his computer. But it has made him a local celebrity. In 2006, he won an AutoShapes art contest, which apparently is a thing. Not bad for a 73-year old retiree who had never used Excel before. The best part about Horiuchi's art is that you can open the original XLS files on your computer (assuming you have Excel—sorry Google Sheets users) to see how the artwork was created. And Horiuchi isn't the only Excel artist. Detroit-based artist Danielle Aubert turned a daily Excel drawing exercise into a book, 16 Months Worth of Drawings in Microsoft Excel. The mathematics group Think Maths even created an application that turns any photo into pixelated art for Excel. I love nerds!

The prototype for the SAT looks nothing like today's version.  

We hope you studied your Latin adjective declensions! The College Board administered its first exam this week in 1901, marking the beginning of the end for the absurdly inefficient admissions process of old.  

Prior to 1900, students had to travel to prospective universities to be evaluated. Universities wrote and administered their own tests, which could more than a week for students to complete—making applications to just one or two schools financially burdensome for everyone involved.  

In 1885, a school principal raised the issue with the National Education Association so a better process could be devised. After 15 years of planning, the College Board was formed. It hoped to standardize high school curricula, and streamline the college application process to make higher education available to a wider range of applicants.  

The 1901 test consisted of essays in several topics: English, French, German, Latin, Greek, history, mathematics, chemistry, and physics. Forget about trying to score a perfect 2400, these students were vying for titles: Excellent, Good, Doubtful, Poor, or Very Poor. The test was administered to a mere 973 students in 69 locations.  

The modern-day SAT was developed in 1925, based on an army intelligence test, and reworked to grade students on a point-based scale. Test-taking numbers have improved considerably since then; nowadays, over 1.5 million students take the SAT each year. We'd grade that "Excellent."