Initial default drop downs and dependent default drop downs

Private Sub Worksheet_Change(ByVal Target As Range)

If Target.Address <> "$B$1" Then Exit Sub

Application.EnableEvents = False

    Range("B3:B6").FormulaR1C1 = _
        "=INDEX(data!R1C1:R25C5,RIGHT(RC[-1],LEN(RC[-1])-4)*1+1,MATCH('Drop Downs'!R1C2,data!R1,0))"
        
        Range("B3:B6").Value = Range("B3:B6").Value
        
Application.EnableEvents = True
End Sub