Excel Function COUPNUM

COUPNUM(settlement, maturity, frequency [,basis])

Returns the number of coupons between the settlement date and the maturity date.

settlement	The settlement date of the security.
maturity	The maturity of the security.
frequency	The number of coupon payments in a year: 1 = annual 2 = semi annual 4 = quarterly
basis	(Optional) The type of day counting to use: 0 = US 30/360 (default) 1 = Actual/Actual 2 = Actual/360 3 = Actual/365 4 = European 30/360

Remarks

* The number returned from this function is always rounded up the nearest whole number.
* The "settlement" is the date a buyer purchases a coupon, such as a bond.
* The "maturity" is the date when the security expires.
* If "settlement" >= "maturity", then #NUM! is returned.
* If "settlement" is not an integer, it is truncated.
* If "settlement" is not a valid date, then #NUM! is returned.
* If "maturity" is not a valid date, then #NUM! is returned.
* If "maturity" is not an integer, it is truncated.
* If the "maturity" date has passed, then #VALUE! is returned.
* If "frequency" is not an integer, it is truncated.
* If "frequency" is any number other than 1, 2 or 4, then #NUM! is returned.
* If "basis" is left blank, then 0 is used.
* If "basis" is not an integer, it is truncated.
* If "basis" < 0, then #NUM! is returned.
* If "basis" > 4, then #NUM! is returned.
* For the Microsoft documentation refer to support.office.com

	A
1	=COUPNUM("1/25/1998","11/15/1999",2,1) = #VALUE!