Option Explicit
Function Y&(¥»ª÷&, ¨C¤ëªá¶O&, ³q¿±#, °t®§#, °h¥ðª÷&)
Dim i&, ¾ã¦~ªá¶O¥[³q¿±&
For i = 1 To 10000
¾ã¦~ªá¶O¥[³q¿± = ¨C¤ëªá¶O * 12 * (1 + ³q¿±) ^ i
¥»ª÷ = ¥»ª÷ - (¾ã¦~ªá¶O¥[³q¿± - (¥»ª÷ * °t®§) - °h¥ðª÷)
If ¥»ª÷ < 0 Then Y = i + 1: Exit For
Next
End Function