Calculation Correction

How did we get into this calculation conundrum? It has to do with a cumulative rounding error in trying to reconcile the Julian calendar with the tropical or astronomical calendar. The Julian calendar, established by Julius Caesar in 46 B.C. lasted from 45 B.C. until A.D. 1582 and stipulated that the year should be 365 days for 3 years in a row, with every 4th year having 366 days. This meant that an average year was 365.25 days. But according to the tropical calendar, the year has 365.24219 days.

Different Kinds of Years

It Adds Up

St. Bede

Gregorian vs Julian Calendar

Gregory XIII

Writer and technologist. Author of fascinating articles about history, tech trends, and pop culture. billpetro.com @billpetro

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