How to Find RD Muture value (Yearly,Half yearly,Quarterly, Monthly)

'call it like
List1.Clear
List1.AddItem RDMature(Val(Text1.Text), Val(Text2.Text), Val(Text3.Text), 12)
List1.AddItem RDMature(Val(Text1.Text), Val(Text2.Text), Val(Text3.Text), 2)
List1.AddItem RDMature(Val(Text1.Text), Val(Text2.Text), Val(Text3.Text), 4)
List1.AddItem RDMature(Val(Text1.Text), Val(Text2.Text), Val(Text3.Text), 1)