Yes, and that's exactly what the lovely and talented TristramEvans and I are discussing — the difference in the system of leap years between the Julian calendar and the Gregorian calendar.Well technically I also have to adjust for leap years too

In the [proleptic] Gregorian calendar leap years [would] have been omitted in AD 100, 200, 300, 500, 600, 700, 900, 1100, 1300, 1400, 1500, 1700, 1800, and 1900, which is fourteen times since JC was assassinated.

So the calculation goes: Caesar was murdered on 15 March 44 BC according to the Julian calendar, which would have been 18 March 44 BC in the proleptic Gregorian calendar. From 18 March 44 BC to 18 March AD 2023 will be 2,066 years, which will be 2 066 × 365 = 754 090 days plus the number of leap years. There would have been 2 066 div 4 = 516 leap years in that span except that the century rule eliminates fourteen of them, so there have been 502, for a total of 754 592 days from the assassination of Caesar to this coming Saturday. 754 589 days from the assassination of Caesar to today.

The easy rule of thumb, which involves some risk of a rounding error of one day, is to multiply the number of years from the Ides of March 44 BC to this coming Saturday by the average length of a Gregorian year, which is 365.2425 days, and then round

*up*. 2 066 × 365.2425 =754 591.005, which rounds up to 754 592. And then you subtract three days wanting until Saturday: 754 589 days from the Ides of March 44 BC (Julian) to 15 March AD 2023 (Gregorian).

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