slow loop! any advice??

[danmcdon]

I have a loop which currently runs 96*19*10 = 18,240 times and it's taking a long time (about 5 minutes). Is this to be expected? Anyone have any advice on how to increase efficiency? Thanks!!

Sub simulations()

'set timer
Dim StartTime As Double
Dim EndTime As Double

StartTime = Timer

Application.ScreenUpdating = False
    'Select toggle sheet to start

Dim iterations As Integer
Dim days As Integer
Dim startdate As Date
Dim securities As Integer

Dim i As Long
Dim j As Integer
Dim d As Long

Dim swap As String
Dim rows As Integer
Dim cols As Integer


iterations = Range("iterations")
days = Range("dates").rows.Count - 1
startdate = DateSerial(2008, 5, 30)
n = 1
securities = Range("swaps").Columns.Count

ReDim Output(1 To iterations) As Long
ReDim Results(1 To securities, 1 To days) As Long

For Each security In Range("swaps")

    swap = security
    Range("swap") = security

    
    'loop through valuation dates
    For d = 1 To days
    
        Range("ValuationDate") = Range("base").Offset(Application.Match(CLng(startdate), Range("dates")) - 2 + d, 0)
    
            'loop through iterations
            For i = 1 To iterations
        
                Range("toggle") = i
            
                Output(i) = Application.WorksheetFunction.Sum(Range("results"))
              
            Next
        
        On Error Resume Next
        Results(n, d) = Application.WorksheetFunction.Average(Output) / Range("spotvaluationdate")
        Erase Output
        ReDim Output(1 To iterations) As Long

    Next
    
    'increment swap number
    n = n + 1

Next

    'paste results
    rows = Application.Match(CLng(startdate), Range("dates"), 0) - 1
    Range(Range("base").Offset(rows, 1), _
          Range("base").Offset(rows + d - 2, securities)) = WorksheetFunction.Transpose(Results)



'display run time
EndTime = Timer - StartTime
MsgBox EndTime


End Sub