explain xkcd - User contributions [en]

2676: Historical Dates

2022-09-24T21:31:09Z

Asterisk: Clarified the LO/OO 1899-12-30 claim

{{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 otherwise undefined numbers in most systems, such as where no value at all has actually been entered into a given spreadsheet cell) 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.)

Spreadsheets store dates as sequential serial numbers so that they can be used in calculations. In Excel, 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 intentionally 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. Most other spreadsheet applications copied the behaviour of Excel to maintain compatibility with it. This leads to the value of 0 in some applications (notably Open- and LibreOffice Calc and Google Spreadsheets) being interpreted as Dec 30th, 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]]

Talk:2676: Historical Dates

2022-09-24T21:25:07Z

Asterisk:

Source for the Excel/Lotus 123 relation with Dec 30th, 1899: https://social.msdn.microsoft.com/Forums/office/en-US/f1eef5fe-ef5e-4ab6-9d92-0998d3fa6e14/what-is-story-behind-december-30-1899-as-base-date?forum=accessdev
[[User:Victor|Victor]] ([[User talk:Victor|talk]]) 08:14, 24 September 2022 (UTC)

I feel this one. My birthday happens to be within 24 hours of [[1179: ISO 8601|1970-01-01]], so I keep getting caught off guard for a moment whenever I see my birthday showing up in one of these contexts. -- [[User:KarMann|KarMann]] ([[User talk:KarMann|talk]]) 08:35, 24 September 2022 (UTC)

We're going to need the date stamp format for 1890 ticker tape for this one. Anyone? [[Special:Contributions/172.70.214.183|172.70.214.183]] 11:59, 24 September 2022 (UTC)
:MM/DD/YY, with leading zeros omitted, and no I don't know why, but I suggest Google Books Ngrams might have a clue as to when that abomination started. [[Special:Contributions/172.69.22.61|172.69.22.61]] 12:03, 24 September 2022 (UTC)
::Not necessarily with pairs of the slash '/' _ . . _ . but also hyphens '-' _ . . . . _ and periods '.' . _ . _ . _ were used as delimiters in MM?DD?YY, which if I remember right dates to the 1500s when accounting ledgers were invented. [[Special:Contributions/172.70.207.8|172.70.207.8]] 12:10, 24 September 2022 (UTC)
::::Are you with the NSA and have a data warehouse of all the ticker tapes ever sent or something? [[Special:Contributions/162.158.166.185|162.158.166.185]] 12:45, 24 September 2022 (UTC)
:::::No, but my great grandparents thought ticker tape parades were littering, because Great Grandma worked in an office and Great Grandpa worked for sanitation, so we have a bunch of boxes in the attic filled with what she was supposed to throw out her window. [[Special:Contributions/172.71.158.75|172.71.158.75]] 12:54, 24 September 2022 (UTC)
:::That would be [https://www.jstor.org/stable/40697544 1299]. But I'm not sure how this is going to help us explain the comic, unless you perhaps are suggesting we enumerate date representation clusters somehow? [[Special:Contributions/172.69.22.61|172.69.22.61]] 12:32, 24 September 2022 (UTC)
:::: Someone should ask GPT-3 for a list of the top ten dates. [[Special:Contributions/172.69.22.71|172.69.22.71]] 12:59, 24 September 2022 (UTC)

Just putting January 2, 2006 here: https://stackoverflow.com/questions/20530327/origin-of-mon-jan-2-150405-mst-2006-in-golang [[Special:Contributions/172.69.22.161|172.69.22.161]] 12:28, 24 September 2022 (UTC)

Do we need a comment about how Pope Gregory XIII obliterated October 5th through 14th, 1582? [[Special:Contributions/172.71.158.25|172.71.158.25]] 13:30, 24 September 2022 (UTC)

In Unix, January 1st, 1970 0h0 is 0. In Excel, December 31st, 1899 is 1. Either Randal forgot December has 31 days (hence December 30th) or he though Excel starts to count at 0 like Unix. For more information in the (probably) intentional bug in Excel https://www.joelonsoftware.com/2006/06/16/my-first-billg-review/ .

In Excel, January 1, 1900 is 1. However, December 30, 1899 is the "epoch" date that you should use if you want to convert a current date (anything on or after March 1, 1900) to a number by "subtracting" the current date minus the epoch date (counting the number of days since the epoch date). The reason it isn't December 31 is because of the above mentioned bug where Excel counts February 29, 1900 as a day even though it actually isn't.
::I just checked it in different versions of Excel, you are right. Meanwhile LO Calc it is Dec 31th 1899... I'll try to edit the explaination to make it more universal. [[User:Asterisk|Asterisk]] ([[User talk:Asterisk|talk]]) 21:11, 24 September 2022 (UTC)
:::In Excel 2002 (XP) it actually interprets it as "1900-01-00" or "January 0, 1900", that's weird [[User:Asterisk|Asterisk]] ([[User talk:Asterisk|talk]]) 21:25, 24 September 2022 (UTC)

Speaking of dates, shouldn’t this one be in the category “Saturday comics”? Or was it still Friday in Hawaii when it came out? [[Special:Contributions/162.158.107.246|162.158.107.246]] 17:57, 24 September 2022 (UTC)
:While uploaded by the bot on 2022-09-24, the xkcd archive (and json data) states that this comic was published on 2022-09-23 —[[User:Theusaf|theusaf]] ([[User talk:Theusaf|talk]]) 18:44, 24 September 2022 (UTC)
::The same thing happened on Monday. The comic didn't show up until Tuesday, but it was still dated Monday. Someone suggested that the book tour has been interfering with Randall's schedule. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:25, 24 September 2022 (UTC)

2676: Historical Dates

2022-09-24T21:18:41Z

Asterisk:

{{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 otherwise undefined numbers in most systems, such as where no value at all has actually been entered into a given spreadsheet cell) 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.)

Spreadsheets store dates as sequential serial numbers so that they can be used in calculations. In Excel, 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 intentionally 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. Most other spreadsheet applications copied the behaviour of Excel to maintain compatibility with it. This leads to the value of 0 in spreadsheets being interpreted as Dec 30th, 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]]

Talk:2676: Historical Dates

2022-09-24T21:11:57Z

Asterisk:

Source for the Excel/Lotus 123 relation with Dec 30th, 1899: https://social.msdn.microsoft.com/Forums/office/en-US/f1eef5fe-ef5e-4ab6-9d92-0998d3fa6e14/what-is-story-behind-december-30-1899-as-base-date?forum=accessdev
[[User:Victor|Victor]] ([[User talk:Victor|talk]]) 08:14, 24 September 2022 (UTC)

I feel this one. My birthday happens to be within 24 hours of [[1179: ISO 8601|1970-01-01]], so I keep getting caught off guard for a moment whenever I see my birthday showing up in one of these contexts. -- [[User:KarMann|KarMann]] ([[User talk:KarMann|talk]]) 08:35, 24 September 2022 (UTC)

We're going to need the date stamp format for 1890 ticker tape for this one. Anyone? [[Special:Contributions/172.70.214.183|172.70.214.183]] 11:59, 24 September 2022 (UTC)
:MM/DD/YY, with leading zeros omitted, and no I don't know why, but I suggest Google Books Ngrams might have a clue as to when that abomination started. [[Special:Contributions/172.69.22.61|172.69.22.61]] 12:03, 24 September 2022 (UTC)
::Not necessarily with pairs of the slash '/' _ . . _ . but also hyphens '-' _ . . . . _ and periods '.' . _ . _ . _ were used as delimiters in MM?DD?YY, which if I remember right dates to the 1500s when accounting ledgers were invented. [[Special:Contributions/172.70.207.8|172.70.207.8]] 12:10, 24 September 2022 (UTC)
::::Are you with the NSA and have a data warehouse of all the ticker tapes ever sent or something? [[Special:Contributions/162.158.166.185|162.158.166.185]] 12:45, 24 September 2022 (UTC)
:::::No, but my great grandparents thought ticker tape parades were littering, because Great Grandma worked in an office and Great Grandpa worked for sanitation, so we have a bunch of boxes in the attic filled with what she was supposed to throw out her window. [[Special:Contributions/172.71.158.75|172.71.158.75]] 12:54, 24 September 2022 (UTC)
:::That would be [https://www.jstor.org/stable/40697544 1299]. But I'm not sure how this is going to help us explain the comic, unless you perhaps are suggesting we enumerate date representation clusters somehow? [[Special:Contributions/172.69.22.61|172.69.22.61]] 12:32, 24 September 2022 (UTC)
:::: Someone should ask GPT-3 for a list of the top ten dates. [[Special:Contributions/172.69.22.71|172.69.22.71]] 12:59, 24 September 2022 (UTC)

Just putting January 2, 2006 here: https://stackoverflow.com/questions/20530327/origin-of-mon-jan-2-150405-mst-2006-in-golang [[Special:Contributions/172.69.22.161|172.69.22.161]] 12:28, 24 September 2022 (UTC)

Do we need a comment about how Pope Gregory XIII obliterated October 5th through 14th, 1582? [[Special:Contributions/172.71.158.25|172.71.158.25]] 13:30, 24 September 2022 (UTC)

In Unix, January 1st, 1970 0h0 is 0. In Excel, December 31st, 1899 is 1. Either Randal forgot December has 31 days (hence December 30th) or he though Excel starts to count at 0 like Unix. For more information in the (probably) intentional bug in Excel https://www.joelonsoftware.com/2006/06/16/my-first-billg-review/ .

In Excel, January 1, 1900 is 1. However, December 30, 1899 is the "epoch" date that you should use if you want to convert a current date (anything on or after March 1, 1900) to a number by "subtracting" the current date minus the epoch date (counting the number of days since the epoch date). The reason it isn't December 31 is because of the above mentioned bug where Excel counts February 29, 1900 as a day even though it actually isn't.
::I just checked it in different versions of Excel, you are right. Meanwhile LO Calc it is Dec 31th 1899... I'll try to edit the explaination to make it more universal. [[User:Asterisk|Asterisk]] ([[User talk:Asterisk|talk]]) 21:11, 24 September 2022 (UTC)

Speaking of dates, shouldn’t this one be in the category “Saturday comics”? Or was it still Friday in Hawaii when it came out? [[Special:Contributions/162.158.107.246|162.158.107.246]] 17:57, 24 September 2022 (UTC)
:While uploaded by the bot on 2022-09-24, the xkcd archive (and json data) states that this comic was published on 2022-09-23 —[[User:Theusaf|theusaf]] ([[User talk:Theusaf|talk]]) 18:44, 24 September 2022 (UTC)