MACRS Depreciation
Per-year MACRS depreciation, accumulated, and book value by class life (half-year convention).
Example
You enter
- Asset cost (USD) 50000
- Class life (years) 5
- Convention half_year
- Year of interest 1
You get
- Year depreciation $10000
- Accumulated $10000
- Book value $40000
Checked against published worked examples from: IRS Pub. 946.
Details, formula, and sources
ScopeIRS Pub 946 Tables A-1.
Formula or tablePer-year depreciation = cost * percentage_table[class_life][year]. Half-year convention bundled (Pub 946 Table A-1). 200% DB switching to straight-line for 3 / 5 / 7 / 10-year classes; 150% DB for 15 / 20-year.
Source and editionIRS Publication 946 Tables A-1 (half-year, 200% DB) and the 15 / 20-year extensions, current edition.
Free accessFree at irs.gov/publications/p946. Table values bundled in calc-accounting.js MACRS_TABLES (data/accounting/macrs-tables.json).
What governsEstimate only. Tax law changes. Confirm with the current IRS publication or a licensed CPA before filing.
API field namescost, class_life, convention, year_of_interest, year_depreciation, accumulated_depreciation, book_value
- Convention half-year (the spec also calls for mid-quarter; only half-year is bundled in the v5 starter)Pub 946 Table A-1
- Class life 3 / 5 / 7 / 10 / 15 / 20 yearPub 946 §4 class lives