2676: Historical Dates

2022-09-24T19:42:19Z

Adaml: /* Explanation */ Fixed incorrect statement that a value of 1.0 in Excel was December 30, 1899. This can be debunked in Excel by entering 1 in a cell and then setting the format to Date -- it comes out as 1/1/00.

{{comic
| number = 2676
| date = September 23, 2022
| title = Historical Dates
| image = historical_dates_2x.png
| imagesize = 305x438px
| noexpand = true
| titletext = Evidence suggests the 1899 transactions occurred as part of a global event centered around a deity associated with the lotus flower.
}}

==Explanation==
{{incomplete|Created by a CONFUSED HISTORIAN BORN ON DECEMBER 30TH - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
Many files and database entries contain a date. When it is not set, it often defaults to the first day in the system.

The default "creation date" of many operating systems and software is Jan 1st, 1970. Which leads to a lot of files wrongly reporting that they were created on this date. This comes from dates being stored as [https://en.wikipedia.org/wiki/Unix_time Unix timestamps], which are defined as the number of seconds since Jan 1st, 1970, 0:00, so a timestamp value of 0 (the default value of integers in most systems) equates to this date.

Dec 30th, 1899 comes from a [https://www.joelonsoftware.com/2006/06/16/my-first-billg-review/ spreadsheet date compatibility issue] between Excel and Lotus 123 (referenced in the title text.)

Excel stores dates as sequential serial numbers so that they can be used in calculations. By default, January 1, 1900 is serial number 1 [https://support.microsoft.com/en-us/office/datevalue-function-df8b07d4-7761-4a93-bc33-b7471bbff252]. Based on that, Excel's integer date representation is the number of days that have passed since December 31, 1899. However, because of a bug carried over from Lotus 1-2-3 where it counts February 29, 1900 as a day even thought it actually was not [https://learn.microsoft.com/en-us/office/troubleshoot/excel/wrongly-assumes-1900-is-leap-year], for any day since then, Excel's integer date representation is actually the number of days that have passed since December 30, 1899. If an application is only considering dates more recent than 1900, a value of 0 could represent December 30, 1899.

Similarly, Microsoft Visual Basic and Visual Basic for Applications (VBA) interpret 0.0 as Dec 30th, 1899.

The historian in the comic presents some research wrongly based only on the number of entries created on those dates. This confusion on the part of the future historian only grows in the title text, where they make the claim that Lotus 123 is, in fact, religious imagery related to some sort of deity, potentially a lotus god, around whom the '1899 event' took place. This confusion may have been at least partially due to China's {{w|White Lotus|White Lotus Religion}}.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Blondie is talking, while pointing to a hologram, representing a timeline with two dates: 1899 and 1970]
:Historical records show millions of business transactions occurred on Dec 30th, 1899.

:This economic activity sparked the digital age, culminating in a "data festival" on Jan 1st, 1970, when many early digital files were created.

:[Caption under the panel:]
:It's going to be weird when historians forget why some dates show up a lot.

{{comic discussion}}

[[Category:Calendar]]
[[Category:Time]]

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2676: Historical Dates