DAYS360

DAYS360(start_date, end_date [,method])

Returns the number of days between two dates, based on 30 day months.

start_date	The first date or starting date of the period.
end_date	The last date or ending date of the period.
method	(Optional) A logical value indicating which method to use: False / 0 = US convention (default) True / 1 = European convention

REMARKS

* The calendar used is based on a 360 day year with twelve 30 day months.
* The "date" arguments can be entered as text strings within quotation marks, as serial numbers or as results of other formulas or functions.
* If "start_date" is the 31st of a month then the 30th of that month is used.
* If "start_date" > "end_date", then a negative number is returned.
* If "start_date" is not a valid date, then #VALUE! is returned.
* If "end_date" is not a valid date, then #VALUE! is returned.
* If "method" is left blank, then False is used.
* If "method" = "US" and the starting date is the last day of a month (28,29,30 or 31), then the 30th day of that month is used.
* If "method" = "US" and the ending date is the last day of a month (28,29,30 or 31), then the 30th day of that month is used.
* If "method" = "US" and the ending date is the last day of a month (28,29,30 or 31) AND the starting date is earlier than the 30th day of a month, then the ending date becomes the 1st day of the next month.
* If "method" = "European" and the starting date is the 31st day of a month, then the 30th day of that month is used.
* If "method" = "European" and the ending date is the 31st day of a month, then the 30th day of that month is used.
* This function is useful for some accountancy systems that use a 360 day calendar.
* The date format can be any of those found on the "Format Cells" dialog box.
* You can use the DAY function to return the day as an integer given a date serial number.
* You can use the DAYS function to return the number of days between two dates.
* You can use the NETWORKDAYS.INTL function to return the number of days excluding weekends and holidays.
* You can use the WORKDAY.INTL function to return a given number of working days before or after a date.
* You can use the YEARFRAC function to return the number of years as a decimal between two dates.
* For the Microsoft documentation refer to support.microsoft.com
* For the Google documentation refer to support.google.com

	A	B
1	=DAYS360("1 Jan 2022","1 Jan 2022") = 0	Saturday, January 01, 2022
2	=DAYS360("1 Jan 2022","2 Jan 2022") = 1	Sunday, January 02, 2022
3	=DAYS360("1/1/2022","9/1/2022") = 8	Monday, January 03, 2022
4	=DAYS360(B1,B9) = 8	Tuesday, January 04, 2022
5	=DAYS360("1 Jan 2022","30 Jan 2022") = 29	Wednesday, January 05, 2022
6	=DAYS360("1 Jan 2022","31 Jan 2022") = 30	Thursday, January 06, 2022
7	=DAYS360("1 Jan 2022","1 Feb 2022") = 30	Friday, January 07, 2022
8	=DAYS360("30 Jan 2022","02 Feb 2022") = 2	Saturday, January 08, 2022
9	=DAYS360("31 Jan 2022","02 Feb 2022") = 2	Sunday, January 09, 2022
10	=DAYS360("31 Jan 2022","02 Feb 2022",TRUE) = 2
11	=DAYS360("31 Jan 2022","02 Feb 2022",FALSE) = 2
12	=DAYS360("1 Jan 2022","31 Dec 2022") = 360
13	=DAYS360("14 Jan 2022","1 Jan 2022") = -13
14	=DAYS360(1/1/2022,31/12/2022) = 0
15	=DAYS360(DATE(2022,1,1),DATE(2022,12,31)) = 360
16	=DAYS360("28 Feb 2022","1 Mar 2022",FALSE) = 1
17	=DAYS360("28 Feb 2022","1 Mar 2022",TRUE) = 3
18	=DAYS360("30 Apr 2022","1 May 2022",FALSE) = 1
19	=DAYS360("30 Apr 2022","1 May 2022",TRUE) = 1
20	=DAYS360("1/30/2022","2/1/2022") = #VALUE!
21	=DAYS360("01/03/2022","31/06/2022",TRUE) = #VALUE!
22	=DAYS360("03/16/2022","03/16/2022") = #VALUE!

3 & 12 - You should always put your dates as a text string rather than just in a date format.
10 - You should always try and use the DATE function to ensure you get the correct value.
16 - How many days are there between "27 Feb 2022" and "1 Mar 2022".