In our office we are working on a project where we want to track certain items weekly for approximately 40 weeks, but maintain individual weekly sheets. We also would like to have each week's sheet use data from the sheet of the preceding week. We have had no problem creating the individual worksheet with the necessary formulas and creating additional weekly sheets within the same file. Our problem comes when we attempt to copy formulas from sheet to sheet in a relative format, particularly with the formula we desire to refer to the previous sheet. Any suggetions would be appreciated.