AMORDEGRC 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.

AMORDEGRC applies an accelerated depreciation coefficient derived from 1/Rate, prorates period 0, and rounds charges to whole units. Its final-period rule is not a simple salvage-floor clamp. Inspect the complete schedule instead of assuming that every returned charge preserves the requested residual value. Release implementation.

AMORDEGRC(Cost;PurchaseDate;FirstPeriodEnd;Salvage;Period;Rate[;Basis])

• Cost: positive acquisition amount. PurchaseDate, FirstPeriodEnd: chronological dates defining the initial period.
• Salvage: nonnegative residual value below Cost. Period: 0 for the initial partial period, then positive whole-number periods.
• Rate: positive annual depreciation rate.
• Basis: optional 0; this implementation supports 0, 1, 3 and 4 and explicitly rejects basis 2. The examples supply whole-number periods.

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 Cost=1000, Salvage=100, Rate=20%, purchase July 1 and first period end December 31, 2024, basis 0 gives charges 200, 320, 192, 115, 69, 52, 0 for periods 0 through 6. The accelerated coefficient is 2, making the applied rate 40%.

Through period 4, charges total 896 and book value is 104. Period 5 then returns 52, leaving book value 52, below the supplied salvage 100. This is the inspected release’s half-book-value ending branch, not a claim that the schedule satisfies an external depreciation rule.

The coefficient depends on implied life L=1/Rate: it is 1 for L<3, 1.5 for 3≤L<5, 2 for 5≤L≤6, and 2.5 above 6. The first charge is the rounded date fraction times the accelerated rate times cost; later ordinary charges are the rounded accelerated rate times remaining book value.

For the stated schedule, after 200 and 320 the book value is 480, giving a rounded charge of 192. The next 115 comes from 288×0.4=115.2. These are whole-unit rounding rules, not merely formatting to zero decimal places. The full-year-end basis-1 example separately returns 399 for period 0.

When its remaining depreciable amount would be exceeded, the helper may return half the current book value for the final requested period, or zero for a later request. That is why replacing the branch with MIN(charge;book value−salvage) would produce a different algorithm.

Use positive cost/rate, chronological dates, sensible salvage and nonnegative whole periods; source rejects basis 2. Invalid or extreme inputs were not executed. Reconcile the sum of charges and resulting book values explicitly before using this implementation in a depreciation worksheet. AMORLINC and DDB are different methods, not drop-in numerical substitutes.

AMORLINC, DDB, DB.

• Function-specific release implementation
• Function calculation helper
• GetYearFrac date-fraction helper
• GetDiffParam date-fraction helper

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.