For most people around the world, Jan. 4 marked just another working day of the New Year. But for most of the world’s top bosses, it was “Fat Cat Wednesday.”

The term was coined by British think tank High Pay Center, which monitors pay at the top of the income distribution. By that afternoon, FTSE 100 bosses had earned more than the typical British worker does in the entire year, it says. The think tank’s calculations were based on the generous assumption that FTSE 100 bosses work 12 hours a day, including three out of every four weekends, and took fewer than 10 days holiday per year.

Using this assumption, along with data from Bloomberg’s Global CEO Pay Index and the average worker pay in several countries, Quartz calculated how quickly the richest CEOs earn the amounts their average countrymen earn in a year. (For the UK, Bloomberg’s average CEO pay was used instead of the High Pay Centre’s CEO median wage.)

South Africa came out on top of the income gap chart. While CEOs in South Africa make far less on average than their American counterparts, their salaries were 541 times more than the average income in their own country. It took CEOs in South Africa just over seven hours to make $13,194, which is the country’s average yearly wage. Assuming Monday, Jan. 2, was a public holiday and they started work at 7:30am on Tuesday, Jan. 3, CEOs in South Africa clocked in the annual average wage by 3pm that day.

The gap between the CEOs and average workers is also particularly extreme in the US. Top US bosses made the country’s annual average wage in over 13 hours, or by roughly 8:45am on Wednesday, Jan. 4. This echoes figures from a study last year, which estimated that the top 500 CEOs earned 340 times the average worker’s wage.

Most CEOs in the top 10 of Bloomberg’s Global Pay Index earned the average annual wage in their country by 6:30pm on Wednesday, Jan. 4. CEOs in Norway and Singapore were the only ones not to; it took CEOs in Norway 39 hours to earn their country’s average annual wage (putting it in hand by 10am Friday, Jan. 6), while CEOs in Singapore earn the average annual wage in 60 hours (Tuesday, Jan. 10, at just past 10:30am, if they took the first full weekend in January off).