I need to Loop the formula below until Column "B" which contains dates is empty. I am stuck and I just can't seem to write the VBA Code to do the Loop until there is no more Dates in Column "B". The formula is smoothing out the yields by using those dates that have a yield.

I hope anyone would be able to help me. Thanks in advance

      A      B       C         D
5   Factor Date    Yield     Input
6    3     May-10   .25 
7    1     Jun-10  
8    2     Jul-10  
9    3     Aug-10   0.2000 
10   1     Sep-10  
11   2     Oct-10  
12   3     Nov-10   0.2418 
13   1     Dec-10  
14   2     Jan-11  
15   3     Feb-11   0.3156 
16   1     Mar-11  
17   2     Apr-11  

.

Sub IsNumeric()


'IF(ISNUMBER(C6),C6,

If Application.IsNumber(range("c6").Value) Then

range("d6").Value = range("c6")


'IF(C6<C5,((OFFSET(C6,2,0)-OFFSET(C6,-1,0))*A6/3+OFFSET(C6,-1,0)),

If range("c6").Select < range("c5").Select Then

range("d6").Value = range("c6").Offset(2, 0).Select - range("c6").Offset(-1, 0).Select * (range("a6").Select / 3) + range("c6").Offset(-1, 0).Select


'IF(C6<>C7,((OFFSET(C6,1,0)-OFFSET(C6,-2,0))*(A6/3)+OFFSET(C6,-2,0)),"")))

If range("c6").Select <> range("c7").Select Then

range("d6").Value = (range("c6").Offset(1, 0).Select) - range("c6").Offset(-2, 0).Select * (range("a6").Select / 3) + range("c6").Offset(-2, 0).Select


Else
range("d6").Value = ""


End If
End If
End If
End Sub