Hi
What you can do is create two formulas to extract the date and year part from the date in parameter field,
then for the month formula of parameter field check for month of jan to give you dec records....
if month({?MY_Date}) = 1 then
month({?MY_Date})
else
Month({?MY_Date})-1
then in your record selection formula
check for
What i have done is to subtract month from the parameter to match the month in table field i.e.Month({?MY_Date})-1
if you could post few more sample records i.e. dates for month of Jan,June, and so on not just one date .... i could test with all possible commbinations,currently what will happen is even when you select 28/02/08 or 01/02/08 you will get record for 31/01/08 5
Cheers
Rahul