Celebrating America’s exclusive mathematical holiday — Pi Day

March 14 is Pi Day, a distinctively American holiday. The holiday’s date, March 14, mirrors the first three digits of pi (3.14), an irrational constant used to measure the circumference or area of a circle. A special moment during Pi Day occurs at 1.59 p.m., in honor of the first six digits of pi (3.14159).

I’ve never gotten mathematicians at Miami excited about Pi Day, but it’s a big deal at Rochester Institute of Technology School of Mathematical Science, where my nephew teaches, as well as with economists and IT personnel at the Federal Reserve Bank of Chicago, where I work part-time. Pi Day festivities feature exciting competitions, such as who can accurately state the most digits from memory.

According to piday.org, pi has been calculated to over 50 trillion digits. The website displays the first one million digits and offers an opportunity to see how many of the first 150 digits you can fill in correctly. Median score is reported to be 37 correct, with 3.2% knowing all 150 digits. I suspect respondents are not a random sample of the population.

The highlight of most Pi Day festivities is the baking, judging and consumption of pies. Pie may be spelled differently than pi, but they are pronounced the same.

Piday.org suggests ordering a pizza to measure its radius, diameter, circumference and area before eating it. A fruit pie is round, but this time of year, with local fruit not yet in season, British-inspired meat pies can be based on local ingredients. Shepherd’s pie, a regular in our household, is usually prepared in a rectangular pan, but a circular one works just as well for Pi Day.

Cook ground meat in oil with minced garlic, onions, and mushrooms. The two best sources of ground beef in Oxford are Jana and Skyp Harmon’s Caraway Farm (available at Oxford’s Farmers Market) and Daniel and Cindy Kramer’s Brookside Family Farms (available at MOON Co-op Market). Local mushrooms are available from Guided By Mushrooms at MOON Co-op and T.A.K.E. Mushrooms at the Farmers Market. Drain the fat and add some tomato sauce (not as much as for spaghetti). Several locally made brands are available.

Meanwhile, peel and quarter several potatoes (locally available from Johnson Family Farm and 7 Wonders Farm at the Farmers Market). Place them in a pot, cover with water, bring to a boil, reduce to medium and cook until the potatoes are done. Drain the water, add milk and a pat of butter, and mash until smooth.

Place the meat mixture in the bottom of a round pan and cover with the mashed potatoes. Score the potato top with a fork and sprinkle with paprika. Bake at 350 for just a few minutes until the top is brown but not burned.

Why is Pi Day a distinctively American holiday? After all, Pi is a Greek letter, and calculating the area and circumference of a circle is universal. According to Wikipedia, the United States is the only country in the world that writes the month before the day. April only has 30 days, so the rest of the world will never experience a 3-1-4 date.

James Rubenstein is president of the Board of Directors for the Oxford Free Press and professor emeritus of geography at Miami University.