Spurious 0.0000000000001 Added to Formula Result in Excel

Say, for instance, you have your running total in Sheet1!A1. Right, so now you create a macro you can run that will take all the totals from the other sheets and sum them.

Let's assume the totals for each sheet are on cell A10 -

Sub updatethesum()
Dim ws As Worksheet
    Dim i As Double
    i = 0
For Each ws In ThisWorkbook.Worksheets

    If ws.Name <> "Sheet1" Then
        i = i + ws.Range("A10")
    End If

Next
Sheets("Sheet1").Range("A1") = i
End Sub

If you're worried someone will put a letter instead of a number in A10 you can restrict the input with something like this -

Sub updatethesum()

Dim ws As Worksheet
    Dim i As Double
    i = 0
    Dim bletter As Boolean

For Each ws In ThisWorkbook.Worksheets

    If ws.Name <> "Sheet1" Then
        bletter = IsNumeric(ws.Range("A10").Value)
            If bletter = True Then
             i = i + ws.Range("A10")
            End If
    End If

Next
Sheets("Sheet1").Range("A1") = i
End Sub