Showing posts from March, 2012

Dates differ for Excel between Mac and Windows

Who knew? The default date system in Excel for a Mac is different than that used on Windows. I was working across spreadsheets, referencing a column from one to a column from another and my results were driving me crazy. First it appeared my results column was just not formatted for dates as I was just getting numbers. But when I changed the column to be formatted for dates, I got dates but they were off by about 4 years. After checking my formula, which I've used countless times ( Lookup values in Excel ), I finally went searching and found this article, Microsoft Excel Date Systems for Windows and Mac . Sure enough, one of the spreadsheets I had created on my Mac while the other came from a Windows user. Bottom line, Windows uses the 1900 date system while Macs use the 1904 date system. Before you create a spreadsheet you can change the date system, but if changed afterward it will also change your dates, so be careful. Read Microsoft Excel Date Systems for Windows and Mac