Colouring Cells Based On Date?

I am currently using a piece of code (within a bigger piece) that colours the dates in two columns based on how close it is to the current date. It works fine but sometimes the sheet it is looking in has over 3500 rows so it is taking for ever (well over 6 mins)

The code is

HTML Code:

Sub ColDate() 'date case opened
application.ScreenUpdating = False
Dim MyRg As Range
Dim F As Range
Dim DateDiff As Long
Set MyRg = Range("g1:h" & Range("H" & Rows.Count).End(xlUp).Row)
For Each F In MyRg

[code]...