Replace your calculation field with the original date field. Then, while in layout mode, select this field and use the data formatting options at the bottom of the inspector's data tab to specify a custom date format to show the month and year as you want here.
Hi PHIL...thanks for the reply but I don't see it as the answer. From other forums I found the calculation as the way of defining records from within a month of a particular year, and consequently is needed to generate a month sub summary. If I just use a date field I won't be able to define records per month for each month, Unless there exists another method to do so. If there is I would love to know....Once again thanks for your help.
You'd use your calculation field for sorting your records into groups by month. But use the original date field in order to display the desired Month Name, Year format.
BTW, when I want to group records by month, I use this calculation:
DateField - Day ( DateField ) + 1
But your's works just as well for the purpose of grouping records by month and year.