COUPDAYS - Daxplained

COUPDAYS is a DAX function that returns the number of days in the coupon period that contains the settlement date.

Syntax

COUPDAYS(
   Settlement,
   Maturity,
   Frequency,
   Basis
)

Argument	Properties	Description
Settlement		The security’s settlement date. The security settlement date is the date after the issue date when the security is traded to the buyer.
Maturity		The security’s maturity date. The maturity date is the date when the security expires.
Frequency		The number of coupon payments per year. For annual payments, frequency = 1; for semiannual, frequency = 2; for quarterly, frequency = 4.
Basis	Optional	The type of day count basis to use.

The number of days in the coupon period that contains the settlement date.

Dates are stored as sequential serial numbers so they can be used in calculations. In DAX, December 30, 1899 is day 0, and January 1, 2008 is 39448 because it is 39,448 days after December 30, 1899.
The settlement date is the date a buyer purchases a coupon, such as a bond. The maturity date is the date when a coupon expires. For example, suppose a 30-year bond is issued on January 1, 2008, and is purchased by a buyer six months later. The issue date would be January 1, 2008, the settlement date would be July 1, 2008, and the maturity date is January 1, 2038, 30 years after the January 1, 2008 issue date.
settlement and maturity are truncated to integers.
frequency and basis are rounded to the nearest integer.
An error is returned if:
- settlement or maturity is not a valid date.
- settlement ≥ maturity.
- frequency is any number other than 1, 2, or 4.
- basis < 0 or basis > 4.
This function is not supported for use in DirectQuery mode when used in calculated columns or row-level security (RLS) rules.

Data	Description
25-Jan-11	Settlement date
15-Nov-11	Maturity date
2	Semiannual coupon (see above)
1	Actual/actual basis (see above)

The following DAX query:

EVALUATE
{
  COUPDAYS(DATE(2011,1,25), DATE(2011,11,15), 2, 1)
}

Returns the number of days in the coupon period that contains the settlement date, for a bond with the terms specified above.

[Value]
181

Other functions related to COUPDAYS are:

Contribute » | Contributors: Rick de Groot
Microsoft documentation: https://learn.microsoft.com/en-us/dax/coupdays-function-dax