Run sub routine when sheet is selected

[AHilgers]

I have the following code in a worksheet.

Private Sub Worksheet_Calculate()
If Range("g16").Value >= 4900 Then
MsgBox ("If the only reason for the hold is the large dollar, use the Large Deposit Exception Notice.")
End If
End Sub

I want the message box to appear only if Sheet 4 is selected. Right now the message box appears when any sheet is selected.

 

[AHilgers]

I figured out a solution.