How to read and evaluate record in formula field

Hi All,

How could we read the data of records in a table and evaluate to get a single value to display in report, through the formula field.

As I am facing this problem to display a value in the report, which I have to get the data from the table from all records having Status as Y, Evaluate each data and sum the evaluated value. At last display the sum in report.

Can this be done in Formula Editor?

If yes please can any one give any sample code.

Thanks and regards