Sumif - Colorindex = 37

I have some data where I have colored certain Values.

I want to write a code that would Sum only if the Color Index is 37.

I have attached the sheet as well as the code.

Can anyone clarify what is wrong?

Code =

Sub Colorindex()


Dim LR As Integer, Counter As Byte, GT As Double

ThisWorkbook.Sheets("Sheet1").Activate

LR = Sheets("Sheet1").Cells(Rows.Count, 1).End(xlUp).Row

For Counter = 1 To LR
 
GT = Application.WorksheetFunction.SumIf(Range("A1:A" & LR), Range("A" & Counter).Interior.Colorindex = 37, (Range("A1:A" & LR)))


Next Counter

End Sub