'##### 変数の定義 #####
Dim i As Integer
Dim freq1 As Integer
Dim freq2 As Integer
・
・

'##### 度数，偏差，分散の計算 #####

For i = 1 To Cells(3, 15).Value Step 1

    If Cells(i + 3, 2).Value >= 155 And Cells(i + 3, 2).Value < 160 Then

        freq1 = freq1 + 1

    ElseIf Cells(i + 3, 2).Value >= 160 And Cells(i + 3, 2).Value < 165 Then

        freq2 = freq2 + 1

    ElseIf ・・・

        ・・・

    End If

Next i