Created function return value 0 only

Hi all,

I had created a function based on the formula as attached but my function return value of 0 only. Please advise where I had gone wrong? Thanks.

MultimodalFnc.jpg

Function MM(ByVal number As Double)

x1 = 1
For i = 1 To 6
x1 = x1 * Sin(number * Pi * 0.05)
Next i

x2 = Power((number - 10) / 80, 2)
x3 = Power(2, 2 * x2)

MM = -2 * (x1 / x3)

End Function