Thanks for your response, but sorry I don't know where to put the information you sent. If I add a formula field {datefield} <=dateadd('d',90,currentdate) it returns values of true or false. If I use Report, then Select Expert, "is less than or equal to" and enter the information you sent in the blank field, it is automatically changed to 'd',90,currentdate.
When I preview the report it still shows action dates that are greater than 90 from today'd date.
Please can you tell me where and how the code should be used. Thanks