Linking Dimension Attribute to Date Dim

Hi all,I have a Person Dimension, and one of its attributes is called First Registration Date. I also have a Sales cube linked to the Person Dimension and Date Dimension. Can anyone please tell me how to create cube calculated member that counts the no of First Registration Dates when I query with the Date hierarchy (Date.Date.FullDate) ?I think the way to achieve this is to link First Registration Date Attribute to Date Dimension in some way?My objective is something like:2014 Jan 135 Feb 643 Mar 742 etc.Thanks in advance!