If you’re patting yourself on the back in response to a study showing South Carolinians are the nation’s most generous coffeehouse tippers, you can put your hand down now. Quartz.com this week released an analysis of tipping data provided by payment service Square; according to the numbers, the national average tip on food and drink is 16.5 percent. But baristas do better as a rule, receiving an average gratuity of 18 percent. In South Carolina, the figure is a whopping 23 percent (although only 45 percent of customers paying via Square leave a tip.) By comparison, the average tip in Hawaii -- the state with the stingiest coffee drinkers -- is 15 percent. Even Quartz concedes the statistics are likely flawed, since they don’t account for the types of businesses which use Square or the tipping proclivities of cash-paying customers. But locally, it’s possible to compare affogatos to affogatos. That’s because Black Tap Coffee is a Square user, allowing a direct comparison of Charleston coffee consumers to their brethren statewide. And it’s clear that the city’s not responsible for driving up barista tips. A Black Tap Coffee staffer who checked the café’s year-to-date sales receipts reports the tips on Square transactions stand at 15.3 percent. So folks dreaming about getting rich by pulling espressos may want to adjust their career goals – or consider moving to Columbia.