I have a workbook with 62 sheets to run my apartment complex. 52 sheets are for the different wk ending dates for the year. Each sheet has information from the previous week and master sheet. The other 10 sheets are the Master and various summary sheets that pull from the 52 week sheets. I now need to make up a 2013 workbook and change the 52 week ending dates. I know I can do a copy of my old workbook and get rid of the source reference but what is the fastest way to change the week ending dates AND when changed, will it change all the formulas that refer to the previous weeks? or what is the faster way to change the formulas to correspond to the new sheet names? I have been able to figure out how to make a new workbook with the 52 wk new ending dates but how do I get the old sheets into the new (blank) sheets and will the formulas automatically change? I hope someone understands what I need. Thanks for any help.