Here’s another great head scratcher in the office debacle - why when you are copying date fields from one sheet to another does Excel feel the need to change the date? It all about the 1904 date format you see. All new sheets created in Excel are automatically set to the 1904 date format whereas all previous versions of Excel were set to the 1900 Date format - it’s an easy fix.

In the sheet that you wish to copy the date to, open up the preferences (Excel -> Preferences). 

You then need to open up the ‘Calculations’ section of the preferences.

Then simple select and uncheck the ‘Use 1904 Date System’ - hey presto, if you copy data from your ‘old’ sheet, it will magically appear correctly in the new sheet!

Note: If you are using a Windows computer, you will need to go to Tools -> Options -> Calculation Tab.