Sub yokin()
   Dim gankin, gankin2 As Long
   Dim rishi As Single
   Dim year As Integer
   
   gankin = Range("c4").Value
   rishi = Range("c5").Value
   
   year = 0
   gankin2 = gankin
   
   Range("f5").Select
   Do While gankin2 <= gankin * 2
     year = year + 1
     gankin2 = gankin * (1 + rishi) ^ year
     ActiveCell.Offset(0, -1).Value = year
     ActiveCell.Offset(0, 0).Value = gankin2
     ActiveCell.Offset(1, 0).Select
   Loop
   MsgBox "元金" & gankin & "円が2倍になるのは" & year & "年後です"
   
End Sub