Using "if then" statements inside a "for" loop in Microsoft VBA - excel

Question

I am trying to pull numerical grade values and convert them into a string which will represent the grade, A >90, B >80, and so on. I planned to use a for loop to gather the values from the spreadsheet and then if then statements to assign the letter designation. Here is the code I have so far.
For i = 1 To 11
' Pull Grade numerical value
Grade = Cells(2 + i, 16).Value
' Assign Numerical Value a script Grade
If Grade > 60 Then
Letter = "D"
If Grade > 70 Then
Letter = "C"
If Grade > 80 Then
Letter = "B"
If Grade > 90 Then
Letter = "A"
Else
Letter = "F"
Exit
' Print the letter grade
Cells(2 + i, 17).Text = Letter
Next i
I keep getting errors either pertaining to "Exit" or to "Next i". I have tried using "End" statements as well but that didn't fix the problems either.

Answer 1

Or just use a formula in column Q:
=IF(P:P>=90,"A",IF(P:P>=80,"B",IF(P:P>=70,"C",IF(P:P>=60,"D","F"))))
so it updates automatically and you don't need to use VBA.
Alternatively you can add a sheet named GradeList with the following data
and use
=INDEX(GradeList!B:B,MATCH(P:P,GradeList!A:A,1))
as formula. This way you can easily edit the numbers/grades later, and it will pick the correct grades automatically:

Answer 2

I would prefer Select Case in this situation. And start the Loop from 3 so you don't need to add 2:
For i = 3 To 11
' Pull Grade numerical value
Grade = Cells(i, 16).Value
' Assign Numerical Value a script Grade
Select Case Grade
Case Is >= 90: letter = "A"
Case Is >= 80: letter = "B"
Case Is >= 70: letter = "C"
Case Is >= 60: letter = "D"
Case Else: letter = "F"
End Select
' Print the letter grade
Cells(i, 17).Value = letter
Next i

Answer 3

Great answers from everyone, but surprised not to see a Select...Case mentioned here. This is a perfect example, perhaps even textbook.
Select...Case evaluates a variable according to a number of criteria and then does whatever is written inside the case statement.
So your code would look like this:
For i = 3 To 13
' Pull Grade numerical value
Grade = Worksheets("YourSheetNameHere").Cells(i, 16).Value 'Change that sheet name
'do our evaluation based on "grade"
Select Case Grade
Case >= 90
Letter = "A"
Case >= 80
Letter = "B"
Case >= 70
Letter = "C"
Case >= 60
Letter = "D"
Case Else
Letter = "F"
End Select
Next i

Answer 4

You have a bunch of problems here.
First exit needs to be end if
Second You need elseif for multiple conditions in the same if statement.
Lastly you need to reorder your ifs. If you have a grade of 90 it would return a "D" as that is the first true statement it encounters.
You might as well just loop from 3 - 13 instead of adding 2 each time aswell. And make sure you use explicit references, it will eventually bite you.
I missed one thing, Make all your comparisons >= Folks won't be happy if their 90 is a B.
For i = 3 To 13
' Pull Grade numerical value
Grade = Worksheets("YourSheetNameHere").Cells(i, 16).Value 'Change that sheet name
' Assign Numerical Value a script Grade
If Grade >= 90 Then
Letter = "A"
elseIf Grade >= 80 Then
Letter = "B"
elseIf Grade >= 70 Then
Letter = "C"
elseIf Grade >= 60 Then
Letter = "D"
Else
Letter = "F"
End if
' Print the letter grade
Worksheets("YourSheetNameHere").Cells(i, 17).value = Letter 'Change that sheet name
Next i

Answer 5

Alternatively, use INDEX and MATCH as Application.Function:
Sub Test()
Dim Grade As Long: Grade = 55
Dim arr1 As Variant: arr1 = Array("A", "B", "C", "D", "F")
Dim arr2 As Variant: arr2 = Array(100, 89, 79, 69, 59)
With Application
Debug.Print .Index(arr1, .Match(Grade, arr2, -1))
End With
End Sub
Or drop the INDEX function, and call the array directly:
With Application
Debug.Print arr1(.Match(Grade, arr2, -1) - 1)
End With
Obviously implement this in your loop/function and write the returned value to your cells. Change Grade variable to see the different values this would return =)

Answer 6

I changed the format of the code to match Jclasley and it works fine, here is my final code:
For i = 1 To 11
' Pull Grade numerical value
Grade = Cells(2 + i, 16).Value
' Assign Numerical Value a script Grade
Select Case Grade
Case Is >= 90
Letter = "A"
Case Is >= 80
Letter = "B"
Case Is >= 70
Letter = "C"
Case Is >= 60
Letter = "D"
Case Else
Letter = "F"
End Select
Cells(2 + i, 17).Value = Letter
Next i
End Sub