Difference between revisions of "Documentation/How Tos/Calc: COUPDAYS function"

Revision as of 08:48, 28 June 2008

COUPDAYS

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

This function is only available if the Analysis AddIn is installed.

Syntax:

COUPDAYS(settlement; maturity; frequency; basis)

settlement: the date of purchase of the security.

maturity: the date on which the security matures (expires).

frequency: number of interest payments per year (1, 2 or 4).

basis: is chosen from a list of options and indicates how the year is to be calculated. Defaults to 0 if omitted.

0 - US method (NASD), 12 months of 30 days each

1 - Actual number of days in months, actual number of days in year

2 - Actual number of days in month, year has 360 days

3 - Actual number of days in month, year has 365 days

4 - European method, 12 months of 30 days each

Example:

COUPDAYS("2007-01-25"; "2009-11-15"; 2; 4)

returns 180. A bond is originally issued on 15 November 1999, with a ten year term; the date of maturity is 15 November 2009. You subsequently purchase it on the secondary market, with a settlement date of 25 January 2007; Interest is paid half-yearly (frequency is 2); thus interest is due on the 15 May and the 15 November each year, during the bond's term. Using basis 4, there are 180 days (= 6 * 30) in the interest period in which the settlement date falls (16 November 2006 to 15 May 2007 inclusive = 6 months).

See also:

COUPDAYSNC, COUPDAYBS

Financial functions

Issues:

• For any basis except 1, the length of the interest period is calculated from the length of a year. Thus COUPDAYS returns the same number of days (derived from the number of interest periods in a year), regardless of settlement date, unless basis = 1, when the exact number of days are returned.
• Both Calc and Excel can return a non-integer number of days (including a fraction) - for example COUPDAYS("2007-01-25"; "2009-11-15"; 2; 3) returns 182.5 (= 365/2).