DB

Summary

DB computes per-period depreciation using a declining-balance rate and an optional first-year month proration.

Remarks

• Parameters: cost, salvage, life, period, and optional month (default 12).
• month must be in 1..=12; life and period must be positive; invalid values return #NUM!.
• life and period are truncated to integers for period checks and iteration.
• The declining rate is rounded to three decimals; if cost <= 0 or salvage <= 0, this implementation uses a rate of 1.0.
• Returned value is the period depreciation amount (generally positive expense, but sign follows provided inputs).

Examples

Related functions

• DDB
• SYD
• SLN
• ACCRINTM
• IPMT
• PPMT

FAQ

How is month used in DB?

month prorates the first-year depreciation; if omitted it defaults to 12.

Why can fractional period inputs behave like integers?

DB truncates life and period to integers for iteration and period bounds.

Runtime metadata