Financial

SYD Function in Excel

Returns the sum-of-years' digits depreciation of an asset for a specified period.

Syntax

  • =SYD(cost, salvage, life, per)

Arguments

  • cost (required): Initial cost of asset
  • salvage (required): Value at end of depreciation
  • life (required): Number of periods
  • per (required): Period to calculate depreciation for

Examples

  • =SYD(10000, 1000, 5, 1) - First year depreciation - Result: $3,000

SYD modeling tips

  • Align rate and period units (annual rate ÷ 12 for monthly models).
  • Use consistent cash-flow signs (outflows negative, inflows positive).
  • Hub: [Financial functions guide](/guides/excel-financial-functions-guide/).

Common errors

  • per must be between 1 and life

Use cases

  • Accelerated depreciation
  • Tax calculations
  • Asset accounting

Frequently asked questions

  • What is SYD (sum-of-years' digits) depreciation? SYD is accelerated depreciation using a fraction based on remaining life. For 5-year life, year 1 uses 5/15, year 2 uses 4/15, etc. (15 = 5+4+3+2+1). It's less aggressive than DDB but still front-loads depreciation.
  • How do I calculate the sum-of-years' digits? Sum = n(n+1)/2 where n is the life. For 5 years: 5×6/2 = 15. Year 1 fraction = 5/15, year 2 = 4/15, year 3 = 3/15, year 4 = 2/15, year 5 = 1/15. Depreciation = (Cost-Salvage) × fraction.
  • When should I use SYD vs DDB? SYD provides smoother declining depreciation than DDB. DDB can result in very low depreciation in later years. SYD is often preferred when you want accelerated depreciation but with more predictable year-over-year changes.

Editorial review

  • Reviewed by Excel.Directory Editorial Team. Updated May 2026.