How To Work With Dates Before 1900 In Excel

The yr 1900 trouble concerns the misinterpretation of years recorded by only their terminal two digits, and whether they occurred before or subsequently the twelvemonth 1900. Unlike the twelvemonth 2000 problem, it is not tied to computer software lonely, since the problem existed before electronic computers did and has besides cropped upwards in manual systems.

The about common issue raised by the year 1900 problem regards people'due south ages. Often, a person's birth year was registered with only two digits, on the assumption that either it was not important exactly how former a person is, or that no one lives longer than ane hundred years. In several countries, peculiarly in Europe, a national identification number was introduced (often in the 1950s), including two-digit information about the birth year.

The largest unwelcome side effect from this is people 100 or more years old being mistaken for young children or in some cases, immature children being mistaken for adults.^[i]

When treatment the year 2000 trouble, measures were sometimes taken to avert or rectify this: modifying the national identification number, for instance. For instance, yr is recorded but with two digits in Bulgarian Uniform civil number; however, a solution was set up every bit early equally the inception of the system in 1975: 20 was added to the month number for an individual built-in before 1900 and 40 for those born in or subsequently 2000.

Microsoft Excel [edit]

Microsoft Excel (using the default 1900 Date System) cannot display dates before the year 1900, although this is not due to a two-digit integer being used to represent the year: Excel uses a floating-point number to store dates and times. The number 1.0 represents January i, 1900, in the 1900 Date System, or Jan ane, 1904, in the 1904 Date System and was the default for Macintosh prior to Excel 2016. Numbers smaller than this display as a #VALUE! error.^[2] ^[3]

For compatibility with Lotus 1-2-3, the 1900 Date System incorrectly accepts the date Feb 29, 1900, yet, 1900 was not a spring twelvemonth. This also has the side effect that for the catamenia Jan 01 1900 to Feb 28 1900, the WEEKDAY part reports incorrect values.^[four]

References [edit]

^ "five-Year-Sometime Boy Summoned For Jury Duty". WBAL-Idiot box. March 8, 2006. Archived from the original on September thirty, 2011. Retrieved March 31, 2017.
^ "Differences between the 1900 and the 1904 date organization". docs.microsoft.com . Retrieved Nov 24, 2019.
^ How to Work With Dates Before 1900 in Excel
^ "Excel incorrectly assumes that the year 1900 is a jump year". Microsoft Docs. May 21, 2020. Retrieved July thirty, 2020.