syd - Financial - VB6Parse Library Reference

VB6 SYD Function

The SYD function returns a Double specifying the sum-of-years digits depreciation of an asset for a specified period.

Syntax

SYD(cost, salvage, life, period)

Parameters

cost: Required. Double specifying initial cost of the asset.
salvage: Required. Double specifying value of the asset at the end of its useful life.
life: Required. Double specifying length of the useful life of the asset.
period: Required. Double specifying period for which asset depreciation is calculated.

All arguments must be positive numbers. The period argument must be in the same units as the life argument.

Returns

Returns a Double specifying the depreciation of an asset for a specific period when using the sum-of-years digits method.

Remarks

The SYD function calculates depreciation using the sum-of-years digits method:

Accelerated depreciation: More depreciation in early years, less in later years
Sum-of-years calculation: For life of 5 years, sum = 5+4+3+2+1 = 15
Period weighting: Year 1 uses 5/15, Year 2 uses 4/15, etc.
Formula: SYD = ((cost - salvage) * (life - period + 1) * 2) / (life * (life + 1))
Depreciable base: cost - salvage (total amount to depreciate)
Declining fraction: Remaining life / sum-of-years digits
Period must be valid: Must be between 1 and life (inclusive)
Consistent units: period and life must use same time units (years, months, etc.)

Sum-of-Years Digits Method

The sum-of-years digits (SYD) method is an accelerated depreciation technique: 1. Calculate the sum of all years: sum = life * (life + 1) / 2 2. For each period, the depreciation fraction is: (life - period + 1) / sum 3. Multiply the fraction by the depreciable amount: (cost - salvage)

Example Calculation

For an asset with cost=$10,000, salvage=$1,000, life=5 years: - Depreciable amount = $10,000 - $1,000 = $9,000 - Sum of years = 5+4+3+2+1 = 15 - Year 1: 5/15 × $9,000 = $3,000 - Year 2: 4/15 × $9,000 = $2,400 - Year 3: 3/15 × $9,000 = $1,800 - Year 4: 2/15 × $9,000 = $1,200 - Year 5: 1/15 × $9,000 = $600 - Total: $9,000 (fully depreciated to salvage value)

When to Use SYD

Technology assets: Equipment that loses value quickly initially
Vehicles: Cars and trucks that depreciate faster when new
Tax advantages: When accelerated depreciation provides tax benefits
Matching principle: When asset productivity is higher in early years
Alternative to DDB: Less aggressive than double-declining balance

Typical Uses

Asset Depreciation: Calculate annual depreciation for financial statements
Tax Calculations: Determine tax-deductible depreciation amounts
Book Value Tracking: Track declining book value of assets over time
Financial Reporting: Generate depreciation schedules for reports
Budget Planning: Estimate future depreciation expenses
Asset Management: Track depreciation for multiple assets
Comparison Analysis: Compare SYD with straight-line or DDB methods
Period Calculations: Calculate depreciation for partial periods

Basic Examples

Example 1: Simple Annual Depreciation

Dim depreciation As Double
Dim cost As Double
Dim salvage As Double
Dim life As Double
Dim year As Double

cost = 10000      ' Initial cost
salvage = 1000    ' Salvage value
life = 5          ' 5-year life
year = 1          ' First year

depreciation = SYD(cost, salvage, life, year)
' depreciation = 3000 (5/15 of 9000)

Example 2: Complete Depreciation Schedule

Sub ShowDepreciationSchedule()
Dim cost As Double
Dim salvage As Double
Dim life As Integer
Dim year As Integer
Dim depreciation As Double
Dim totalDep As Double

cost = 50000
salvage = 5000
life = 10
totalDep = 0

For year = 1 To life
depreciation = SYD(cost, salvage, life, year)
totalDep = totalDep + depreciation
Debug.Print "Year " & year & ": $" & Format$(depreciation, "#,##0.00")
Next year

Debug.Print "Total Depreciation: $" & Format$(totalDep, "#,##0.00")
End Sub

Example 3: Monthly Depreciation

Function CalculateMonthlyDepreciation(cost As Double, salvage As Double, _
lifeYears As Integer, month As Integer) As Double
Dim lifeMonths As Integer
lifeMonths = lifeYears * 12

' Calculate depreciation for the specific month
CalculateMonthlyDepreciation = SYD(cost, salvage, lifeMonths, month)
End Function

Example 4: Book Value Calculation

Function CalculateBookValue(cost As Double, salvage As Double, _
life As Integer, currentPeriod As Integer) As Double
Dim period As Integer
Dim totalDepreciation As Double

totalDepreciation = 0
For period = 1 To currentPeriod
totalDepreciation = totalDepreciation + SYD(cost, salvage, life, period)
Next period

CalculateBookValue = cost - totalDepreciation
End Function

Common Patterns

Pattern 1: Depreciation Schedule Generator

Function GenerateDepreciationSchedule(cost As Double, salvage As Double, _
life As Integer) As Variant
Dim schedule() As Double
Dim period As Integer

ReDim schedule(1 To life)

For period = 1 To life
schedule(period) = SYD(cost, salvage, life, period)
Next period

GenerateDepreciationSchedule = schedule
End Function

Pattern 2: Partial Year Depreciation

Function CalculatePartialYearDepreciation(cost As Double, salvage As Double, _
life As Integer, year As Integer, _
monthsInYear As Integer) As Double
Dim fullYearDep As Double

fullYearDep = SYD(cost, salvage, life, year)
CalculatePartialYearDepreciation = fullYearDep * (monthsInYear / 12)
End Function

Pattern 3: Remaining Depreciable Amount

Function GetRemainingDepreciation(cost As Double, salvage As Double, _
life As Integer, currentPeriod As Integer) As Double
Dim period As Integer
Dim accumulatedDep As Double

accumulatedDep = 0
For period = 1 To currentPeriod
accumulatedDep = accumulatedDep + SYD(cost, salvage, life, period)
Next period

GetRemainingDepreciation = (cost - salvage) - accumulatedDep
End Function

Pattern 4: Compare Depreciation Methods

Sub CompareDepreciationMethods(cost As Double, salvage As Double, life As Integer)
Dim period As Integer
Dim sydDep As Double
Dim slnDep As Double
Dim ddbDep As Double

Debug.Print "Period", "SYD", "SLN", "DDB"

For period = 1 To life
sydDep = SYD(cost, salvage, life, period)
slnDep = SLN(cost, salvage, life)
ddbDep = DDB(cost, salvage, life, period)

Debug.Print period, Format$(sydDep, "#,##0.00"), _
Format$(slnDep, "#,##0.00"), _
Format$(ddbDep, "#,##0.00")
Next period
End Sub

Pattern 5: Quarterly Depreciation

Function GetQuarterlyDepreciation(cost As Double, salvage As Double, _
lifeYears As Integer, quarter As Integer) As Double
Dim lifeQuarters As Integer
lifeQuarters = lifeYears * 4

GetQuarterlyDepreciation = SYD(cost, salvage, lifeQuarters, quarter)
End Function

Pattern 6: Accumulated Depreciation

Function GetAccumulatedDepreciation(cost As Double, salvage As Double, _
life As Integer, throughPeriod As Integer) As Double
Dim period As Integer
Dim total As Double

total = 0
For period = 1 To throughPeriod
total = total + SYD(cost, salvage, life, period)
Next period

GetAccumulatedDepreciation = total
End Function

Pattern 7: Depreciation Percentage

Function GetDepreciationPercentage(cost As Double, salvage As Double, _
life As Integer, period As Integer) As Double
Dim depreciableBase As Double
Dim periodDep As Double

depreciableBase = cost - salvage
periodDep = SYD(cost, salvage, life, period)

If depreciableBase > 0 Then
GetDepreciationPercentage = (periodDep / depreciableBase) * 100
Else
GetDepreciationPercentage = 0
End If
End Function

Pattern 8: Multi-Asset Depreciation

Function CalculateTotalDepreciation(costs() As Double, salvages() As Double, _
lives() As Integer, period As Integer) As Double
Dim i As Integer
Dim total As Double

total = 0
For i = LBound(costs) To UBound(costs)
total = total + SYD(costs(i), salvages(i), lives(i), period)
Next i

CalculateTotalDepreciation = total
End Function

Pattern 9: Validate Depreciation Parameters

Function ValidateDepreciationParams(cost As Double, salvage As Double, _
life As Double, period As Double) As Boolean
ValidateDepreciationParams = (cost > 0) And (salvage >= 0) And _
(life > 0) And (period > 0) And _
(period <= life) And (cost > salvage)
End Function

Pattern 10: Format Depreciation Report

Function FormatDepreciationLine(period As Integer, cost As Double, _
salvage As Double, life As Integer) As String
Dim depreciation As Double
Dim accumulated As Double
Dim bookValue As Double
Dim i As Integer

depreciation = SYD(cost, salvage, life, period)

accumulated = 0
For i = 1 To period
accumulated = accumulated + SYD(cost, salvage, life, i)
Next i

bookValue = cost - accumulated

FormatDepreciationLine = Format$(period, "0") & vbTab & _
Format$(depreciation, "#,##0.00") & vbTab & _
Format$(accumulated, "#,##0.00") & vbTab & _
Format$(bookValue, "#,##0.00")
End Function

Advanced Usage

Example 1: Asset Depreciation Manager Class

' Class: AssetDepreciationManager
' Manages depreciation calculations for assets using SYD method
Option Explicit

Private m_Cost As Double
Private m_Salvage As Double
Private m_Life As Integer
Private m_CurrentPeriod As Integer

Public Sub Initialize(cost As Double, salvage As Double, life As Integer)
If cost <= salvage Then
Err.Raise 5, , "Cost must be greater than salvage value"
End If
If life <= 0 Then
Err.Raise 5, , "Life must be greater than zero"
End If

m_Cost = cost
m_Salvage = salvage
m_Life = life
m_CurrentPeriod = 0
End Sub

Public Function GetDepreciation(period As Integer) As Double
If period < 1 Or period > m_Life Then
Err.Raise 5, , "Period must be between 1 and " & m_Life
End If

GetDepreciation = SYD(m_Cost, m_Salvage, m_Life, period)
End Function

Public Function GetAccumulatedDepreciation(throughPeriod As Integer) As Double
Dim period As Integer
Dim total As Double

total = 0
For period = 1 To throughPeriod
total = total + GetDepreciation(period)
Next period

GetAccumulatedDepreciation = total
End Function

Public Function GetBookValue(atPeriod As Integer) As Double
GetBookValue = m_Cost - GetAccumulatedDepreciation(atPeriod)
End Function

Public Function GetDepreciationSchedule() As Variant
Dim schedule() As Variant
Dim period As Integer
Dim accumulated As Double

ReDim schedule(0 To m_Life, 0 To 3) ' Period, Depreciation, Accumulated, Book Value

schedule(0, 0) = "Period"
schedule(0, 1) = "Depreciation"
schedule(0, 2) = "Accumulated"
schedule(0, 3) = "Book Value"

accumulated = 0
For period = 1 To m_Life
Dim dep As Double
dep = GetDepreciation(period)
accumulated = accumulated + dep

schedule(period, 0) = period
schedule(period, 1) = dep
schedule(period, 2) = accumulated
schedule(period, 3) = m_Cost - accumulated
Next period

GetDepreciationSchedule = schedule
End Function

Public Property Get Cost() As Double
Cost = m_Cost
End Property

Public Property Get SalvageValue() As Double
SalvageValue = m_Salvage
End Property

Public Property Get UsefulLife() As Integer
UsefulLife = m_Life
End Property

Example 2: Depreciation Calculator Module

' Module: DepreciationCalculator
' Provides comprehensive depreciation calculation utilities
Option Explicit

Public Function CalculateFullSchedule(cost As Double, salvage As Double, _
life As Integer) As String
Dim period As Integer
Dim output As String
Dim depreciation As Double
Dim accumulated As Double
Dim bookValue As Double

output = "Period" & vbTab & "Depreciation" & vbTab & _
"Accumulated" & vbTab & "Book Value" & vbCrLf
output = output & String(60, "-") & vbCrLf

accumulated = 0
For period = 1 To life
depreciation = SYD(cost, salvage, life, period)
accumulated = accumulated + depreciation
bookValue = cost - accumulated

output = output & period & vbTab & _
Format$(depreciation, "$#,##0.00") & vbTab & _
Format$(accumulated, "$#,##0.00") & vbTab & _
Format$(bookValue, "$#,##0.00") & vbCrLf
Next period

CalculateFullSchedule = output
End Function

Public Function CompareToStraightLine(cost As Double, salvage As Double, _
life As Integer, period As Integer) As Double
Dim sydDep As Double
Dim slnDep As Double

sydDep = SYD(cost, salvage, life, period)
slnDep = SLN(cost, salvage, life)

CompareToStraightLine = sydDep - slnDep
End Function

Public Function CalculateFirstYearDepreciation(cost As Double, salvage As Double, _
life As Integer, _
purchaseMonth As Integer) As Double
Dim monthsInFirstYear As Integer
Dim fullYearDep As Double

monthsInFirstYear = 13 - purchaseMonth
fullYearDep = SYD(cost, salvage, life, 1)

CalculateFirstYearDepreciation = fullYearDep * (monthsInFirstYear / 12)
End Function

Public Function GetDepreciationRate(life As Integer, period As Integer) As Double
Dim sumOfYears As Integer
Dim remainingLife As Integer

sumOfYears = life * (life + 1) / 2
remainingLife = life - period + 1

GetDepreciationRate = remainingLife / sumOfYears
End Function

Example 3: Multi-Asset Tracker Class

' Class: MultiAssetTracker
' Tracks depreciation for multiple assets
Option Explicit

Private Type AssetInfo
Name As String
Cost As Double
Salvage As Double
Life As Integer
PurchaseDate As Date
End Type

Private m_Assets() As AssetInfo
Private m_AssetCount As Integer

Public Sub Initialize()
m_AssetCount = 0
ReDim m_Assets(0 To 9)
End Sub

Public Sub AddAsset(name As String, cost As Double, salvage As Double, _
life As Integer, purchaseDate As Date)
If m_AssetCount >= UBound(m_Assets) Then
ReDim Preserve m_Assets(0 To UBound(m_Assets) * 2)
End If

With m_Assets(m_AssetCount)
.Name = name
.Cost = cost
.Salvage = salvage
.Life = life
.PurchaseDate = purchaseDate
End With

m_AssetCount = m_AssetCount + 1
End Sub

Public Function GetTotalDepreciation(forYear As Integer) As Double
Dim i As Integer
Dim total As Double
Dim period As Integer

total = 0
For i = 0 To m_AssetCount - 1
period = forYear - Year(m_Assets(i).PurchaseDate) + 1
If period >= 1 And period <= m_Assets(i).Life Then
total = total + SYD(m_Assets(i).Cost, m_Assets(i).Salvage, _
m_Assets(i).Life, period)
End If
Next i

GetTotalDepreciation = total
End Function

Public Function GetAssetDepreciation(assetIndex As Integer, period As Integer) As Double
If assetIndex < 0 Or assetIndex >= m_AssetCount Then
Err.Raise 9, , "Invalid asset index"
End If

With m_Assets(assetIndex)
If period < 1 Or period > .Life Then
GetAssetDepreciation = 0
Else
GetAssetDepreciation = SYD(.Cost, .Salvage, .Life, period)
End If
End With
End Function

Public Property Get AssetCount() As Integer
AssetCount = m_AssetCount
End Property

Example 4: Tax Depreciation Reporter

' Module: TaxDepreciationReporter
' Generates tax depreciation reports using SYD method
Option Explicit

Public Function GenerateTaxReport(assetName As String, cost As Double, _
salvage As Double, life As Integer, _
taxYear As Integer) As String
Dim report As String
Dim currentYear As Integer
Dim depreciation As Double
Dim accumulated As Double

report = "Tax Depreciation Report - " & assetName & vbCrLf
report = report & "Method: Sum-of-Years Digits (SYD)" & vbCrLf
report = report & "Cost: " & Format$(cost, "$#,##0.00") & vbCrLf
report = report & "Salvage: " & Format$(salvage, "$#,##0.00") & vbCrLf
report = report & "Life: " & life & " years" & vbCrLf & vbCrLf

accumulated = 0
For currentYear = 1 To taxYear
depreciation = SYD(cost, salvage, life, currentYear)
accumulated = accumulated + depreciation
Next currentYear

report = report & "Depreciation for Year " & taxYear & ": " & _
Format$(SYD(cost, salvage, life, taxYear), "$#,##0.00") & vbCrLf
report = report & "Accumulated Depreciation: " & _
Format$(accumulated, "$#,##0.00") & vbCrLf
report = report & "Book Value: " & _
Format$(cost - accumulated, "$#,##0.00") & vbCrLf

GenerateTaxReport = report
End Function

Public Function ExportToCSV(cost As Double, salvage As Double, life As Integer) As String
Dim csv As String
Dim period As Integer
Dim depreciation As Double
Dim accumulated As Double

csv = "Period,Depreciation,Accumulated,Book Value" & vbCrLf

accumulated = 0
For period = 1 To life
depreciation = SYD(cost, salvage, life, period)
accumulated = accumulated + depreciation

csv = csv & period & "," & _
Round(depreciation, 2) & "," & _
Round(accumulated, 2) & "," & _
Round(cost - accumulated, 2) & vbCrLf
Next period

ExportToCSV = csv
End Function

Public Function CalculateTaxSavings(cost As Double, salvage As Double, _
life As Integer, taxRate As Double) As Variant
Dim period As Integer
Dim savings() As Double
Dim depreciation As Double

ReDim savings(1 To life)

For period = 1 To life
depreciation = SYD(cost, salvage, life, period)
savings(period) = depreciation * taxRate
Next period

CalculateTaxSavings = savings
End Function

Error Handling

The SYD function can raise the following errors:

Error 5 (Invalid procedure call or argument): If any argument is negative, or if period > life, or if cost <= salvage
Error 11 (Division by zero): If life = 0
Error 13 (Type mismatch): If arguments are not numeric

Performance Notes

Very fast calculation using direct formula
No iterative computation required (unlike accumulated depreciation)
Constant time O(1) for single period calculation
For full schedule, O(n) where n is the life of the asset
More efficient than DDB for certain tax scenarios

Best Practices

Validate inputs before calling SYD (cost > salvage, life > 0, period valid)
Use consistent units for period and life (both in years, months, or quarters)
Handle salvage = 0 as valid (fully depreciate to zero)
Cache schedules if calculating multiple periods for same asset
Round appropriately for financial reporting (typically 2 decimal places)
Document assumptions about partial periods and mid-year conventions
Compare methods (SYD, SLN, DDB) to choose appropriate one
Consider tax implications when choosing depreciation method
Track accumulated depreciation separately for audit purposes
Validate period range to avoid errors (1 to life inclusive)

Comparison Table

Method	Pattern	Early Years	Later Years	Calculation
SYD	Accelerated	Higher	Lower	Sum-of-years formula
DDB	Accelerated	Highest	Lowest	Double rate
SLN	Straight-line	Equal	Equal	(Cost-Salvage)/Life

Platform Notes

Available in VB6 and VBA
Not available in VBScript
Returns Double precision floating-point
Part of the Financial functions library
Requires all arguments to be positive (except salvage can be zero)

Limitations

Cannot handle negative values for cost, salvage, or life
Period must be between 1 and life (inclusive)
Does not handle mid-period conventions automatically
No built-in support for asset disposals or write-offs
Salvage value must be less than cost
No automatic switching to straight-line method
Does not account for bonus depreciation or special tax rules