How to compare rows in excel and carry out if statment

Question

I have a spreadsheet where I need to calculate the number of times something has been done to a particular area, I know that when certain criteria exists a field in another spreadsheet should be incremented.

for i to rows.length
   if Cell(A,i) == Cell(A,i+1) AND Cell(D,i) != Cell(D,i+1)
      otherspreadsheet.field++
   else if Cell(A,i) != Cell(A,i+1) 
      otherspreadsheet.field++ 

I don't know how to use vba with Microsoft excel, any help would be greatly appreciated.

+++

I was playing about with the code you provided me to get familiar and eventually figure this problem. The strYear doesn't seem to work, strYear = InputBox("enter year"). If I enter 2014, the count comes out as 0. However if I replace the code below from "strYear" to 2014 then it works.

With MySheet
For i = 4 To LastRow

    If .Cells(i, "AA").Value = "strYear" Then
        GreensFCounter = GreensFCounter + 1
    Else
        GreensFCounter = GreensFCounter
    End If
Next i
End With
MsgBox (GreensFCounter)

Answer 1

The code below is untested, but heavily commented -- I think it will answer your questions as it moves through each section.

A quick note though: you're comparing a cell to the next cell below it, right? On the surface that seems OK, but one corner case you need to consider is the end of the range: you'll be comparing to an empty cell.

Option Explicit
Sub CheckCellsAndTrackResults()

Dim i As Long, LastRow As Long
Dim Counter1 As Long, Counter2 As Long
Dim MySheet As Worksheet

'initialize our counter variables
Counter1 = 0
Counter2 = 0

'lets assume the comparison is happening on Sheet1
Set MySheet = ThisWorkbook.Worksheets("Sheet1")

'identify the last row for our loop
LastRow = MySheet.Cells.Find("*", SearchOrder:=xlByRows, SearchDirection:=xlPrevious).Row

'NOTES:
'use a single equal sign ("=") for equivalent
'use less/greater ("<>") for not equivalent

'lets loop through rows 1 to the last row using a
'cool little VBA construct, a With...End With qualifier,
'to make some of our cell-checking easier to write:
With MySheet
    For i = 1 To LastRow
        If .Cells(1, i).Value = .Cells(1, i + 1).Value And _
        .Cells(4, i).Value <> .Cells(4, i + 1).Value Then
            Counter1 = Counter1 + 1
        ElseIf .Cells(1, i).Value <> .Cells(1, i + 1) Then
            Counter2 = Counter2 + 1
        Else
            'maybe do something else here?
        End
    Next i
End With

'finally, we can write out the counter results somewhere
'like this:
'MySheet.Cells(x, y) = Counter1
'MySheet.Cells(p, q) = Counter2

End Sub