# The Excel COUPNUM Function

Related Function:
COUPDAYS

## Basic Description

The Excel COUPNUM function calculates the number of coupons payable, between a security's settlement date and maturity date, rounded up to the nearest whole coupon.

The syntax of the function is :

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

Where the arguments are as follows:

settlement-The settlement date of the security
maturity-The maturity date of the security
frequency-

The number of coupon payments per year. This must be one of the following values:

 1 - Annually 2 - Semi-Annually 4 - Quarterly
[basis]-An optional argument which specifies the day count basis to be used in the calculation.
This can be any of the following values :
BasisDay Count Basis
0 (or omitted)US (NASD) 30/360
1actual/actual
2actual/360
3actual/365
4European 30/360
The financial day count basis rules are explained in detail on the Wikipedia Day Count Convention page

Note that the settlement and maturity dates should be input to the Coupnum function as either:

• References to cells containing dates
or
• Dates returned from formulas

Warning:

• If you attempt to input dates as text, these may be interpreted differently, depending on the date system and date interpretation settings on your computer.
• Whilst you can input dates as serial numbers, this is not advised, as the serial numbers used to represent dates, vary across different computer systems.

## Excel Coupnum Function Example

Cell A3 of the spreadsheet below shows the Excel Coupnum function, used to calculate the number of coupon payments for a security that uses the US (NASD) 30/360 day count basis, has the settlement date 01-Jan-2011, the maturity date 25-Oct-2012, and 4 coupon payments per year.

Formulas:
A
101-Jan-2011
225-Oct-2012
3=COUPNUM( A1, A2, 4 )
Results:
A
101-Jan-2011
225-Oct-2012
38

In the above example :

• As recommended, the settlement and maturity dates have been input as references to cells containing dates.
• As the [basis] argument has been omitted from the function, the default value 0 (denoting the US (NADS) 30/360 day count basis) is used.

More details and examples of the Excel Coupnum function are provided on the Microsoft Office website.

## Coupnum Function Errors

If an error is returned from the Excel Coupnum Function, this is most likely to be one of the following:

Common Errors
 #VALUE! - Occurs if either:the settlement date or the maturity date is not a valid Excel datethe frequency or the [basis] argument is non-numeric #NUM! - Occurs if either:the supplied settlement date is ≥ maturity datethe supplied frequency argument is any number other than 1, 2 or 4the supplied [basis] argument is any number other than 0, 1, 2, 3 or 4 #NAME? - Occurs when Analysis ToolPak add-in is not enabled in your Excel.You will need to enable the add-in if you want to use the Excel Coupnum function.