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The most common issue raised by the year 1900 problem regards people's ages. Often, a person's birth year was registered with only two digits, on the assumption that either it was not important exactly how old a person is, or that no one lives longer than one hundred years. In several countries,
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number to store dates and times. The number 1.0 represents the first second of
January 1, 1900, in the 1900 Date System (or January 2, 1904, in the 1904 Date System – the default for Macintosh prior to Excel 2016). Numbers smaller than this display as a
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When handling the year 2000 problem, measures were sometimes taken to avoid or rectify this: modifying the national identification number, for instance. For example, year is recorded only with two digits in
Bulgarian
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The largest unwelcome side effect from this is people 100 or more years old being mistaken for young children or in some cases, young children being mistaken for adults.
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concerns the misinterpretation of years recorded by only their last two digits, and whether they occurred before or after the year 1900. Unlike the
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304:"Excel incorrectly assumes that the year 1900 is a leap year"
268:"Differences between the 1900 and the 1904 date system"
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292:How to Work With Dates Before 1900 in Excel
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128:Learn how and when to remove this message
244:. WBAL-TV. March 8, 2006. Archived from
152:alone, since the problem existed before
242:"5-Year-Old Boy Summoned For Jury Duty"
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66:adding citations to reliable sources
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495:Time formatting and storage bugs
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162:national identification number
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408:Binary storage related
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356:Year-related problems
248:on September 30, 2011
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173:Uniform civil number
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62:improve this article
464:Time code ambiguity
415:2036 NTP wraparound
394:Year 10,000 problem
77:"Year 1900 problem"
16:Time formatting bug
272:docs.microsoft.com
222:Perpetual calendar
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446:Year 2010 problem
425:Year 2108 problem
420:Year 2038 problem
399:Leap year problem
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379:Year 2011 problem
374:Year 2000 problem
369:Year 1900 problem
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60:Please help
55:verification
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217:System time
200:Lotus 1-2-3
27:version of
484:Categories
228:References
88:newspapers
252:March 31,
118:July 2024
314:July 30,
206:See also
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193:#VALUE!
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