COUPDAYSNC Function (OpenOffice Calc)

• Introduced: First release not established; documented by OpenOffice.org 3.3.
• Supported in: Apache OpenOffice 4.1.16; this is a verified release, not a final supported version.
• Scope: Desktop Calc, English function names and semicolon-separated formulas.
• Checked: October 14, 2026. Eight ordinary reference formulas were recalculated from generated ODF in 4.1.16 on Linux x86-64, Build 9816. Source and independent arithmetic were checked.

COUPDAYSNC returns the day-count distance from settlement to the next coupon date on a regular maturity-anchored schedule. The next coupon is strictly later than settlement. The function returns a count, whereas COUPNCD returns a date serial. Release implementation.

COUPDAYSNC(Settlement;Maturity;Frequency[;Basis])

• Settlement: date at which the regular coupon schedule is evaluated.
• Maturity: later final coupon date; the schedule is anchored to this date.
• Frequency: 1, 2 or 4 payments per year.
• Basis: optional, defaults to 0: US 30/360. Other values are 1 actual/actual, 2 actual/360, 3 actual/365 and 4 European 30/360. The functions implement the release-specific rules discussed below.

The native column contains saved 4.1.16 results; independent references use high-precision arithmetic and the stated source rules. Values are shown to twelve decimal places where needed. Enter DATE expressions directly rather than locale-dependent date text.

For settlement March 15, 2024 and a semiannual schedule ending December 31, 2025, the next coupon is June 30, 2024. Bases 1, 2 and 3 return the actual 107 remaining calendar days. Bases 0 and 4 return 105 convention-based units.

At settlement June 30, 2024, the next coupon advances to December 31, 2024; actual/actual returns 184, not zero. For quarterly payments at January 15, 2024, the next date is March 31 and the actual count is 76.

The two 30/360 modes compute this result as COUPDAYS-COUPDAYBS. The first example therefore gives 180−75=105. The three actual-day modes instead measure settlement to the next coupon directly.

This is why subtracting COUPDAYBS from COUPDAYS is not a universal replacement. Under basis 2, 180−75=105 but COUPDAYSNC returns 107; under basis 3, 182.5−75=107.5 but the returned actual count is still 107. The guide’s tested values expose the difference rather than assuming all period components use the same denominator.

The next-date search moves in whole coupon months while preserving the maturity anchor’s day or month-end behavior. An annual schedule ending February 28, 2025 yields a 30/360 remainder of 345 at March 15, 2024. That value is a convention count, not a claim that 345 calendar days separate the dates.

Settlement must precede maturity; use frequency 1, 2 or 4 and basis 0–4. All native examples are ordinary valid date-only inputs. Irregular schedules, invalid parameters and fractional-date conversions were not tested. Do not confuse a remaining day count with the number of payments or a discount factor.

COUPNCD, COUPDAYBS, COUPDAYS.

• Function-specific release implementation
• GetCoupdaysnc schedule/date helper
• lcl_GetCouppcd schedule/date helper
• ScaDate::setDay schedule/date helper
• ScaDate::getDate schedule/date helper
• ScaDate::getDiff schedule/date helper
• GetCoupdays schedule/date helper
• GetCoupdaybs schedule/date helper
• lcl_GetCoupncd schedule/date helper
• Maturity month-end preservation
• Optional basis conversion and validation

The generated ODF produced the informational load warning “Not all attributes could be read.” The sheet was hard-recalculated and saved separately. All eight ordinary function identities, inputs and results were reconciled; a stale SUM cache changed from 999999 to 3 and an uncached SUM returned 7. This establishes the stated examples, not every workbook style or invalid input. Other explanatory identities are independent calculations. The authoring-tool XLSX was not executed in OpenOffice, and its preview values are not the native results reported here.