Every day is a “National Day” for something. They’re the modern-day equivalent of “Saint’s” days in this 21st century era of brand messaging and the thirst to go viral, days that most people remain unaware of but happen literally every day.

According to the National Day calendar, Wednesday was National Different Colored Eyes Day, and National Pecan Pie Day. Thursday is National French Fry Day and also National Beans ‘N’ Franks Day.

Friday is the very civilized National Grand Marnier Day—though it doesn’t appear to be on their website. It could get a little wild—the 80 proof liqueur shares the day with National Nude Day and National Tape Measure Day.

Unlike Saint’s days, National Days have brands on their sides, tirelessly pushed by brands on social media and other advertising means, so this information is communicated to the public. (Blue Bell is introducing its new ice cream flavor – Sweet ‘n Salty Crunch– to coincide with National Ice Cream Day). And it can actually work.

National Ice Cream day actually works

Companies creating or pushing these special days can get a meaningful bump (and ice cream lovers can get deals on Ben & Jerry’s and Carvel). Every year, apparently, the third Sunday in July (July 16 this year) is National Ice Cream Day, and it’s the most popular day of the year to buy ice cream, according to data from Square, a popular method for handling credit card payment services for small businesses like ice cream shops.

Last year, the 2,500 ice cream shops that use Square’s card readers saw a 50% spike in sales on National Ice Cream Day compared to the rest of July, and that third week was the biggest week of the year.

Square’s analysis also found some other interesting things about how America eats ice cream. Adjusted for population, the top five states for ice cream consumption per capita were Hawaii, Connecticut, Wisconsin, Colorado, and Oregon. Chocolate beats vanilla by a factor of almost three to one, and mint by 10 to one. And cones are twice as popular as cups.

Ethan Wolff-Mann is a writer at Yahoo Finance focusing on consumer issues, tech, and personal finance. Follow him on Twitter @ewolffmann. Got a tip? Send it to tips@yahoo-inc.com.

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