Something strange with date calculations

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Occasional Visitor

It seems like Excel doesn't count the 31st December as the 365th day in a common year. Instead it is using the number of day in a leap year (366 days) to caculate its dates.
When I was transforming the number of days, I realise that the result is one day off.
If 1 is 1st Jan 1900, then 365 should be 31st Dec 1900, since 1900 has 365 days.

2 Replies

 


If 1 is 1st Jan 1900, then 365 should be 31st Dec 1900, since 1900 has 365 days.

Not in Excel. In Excel the year 1900 is a leap year.