To find out the difference between dates, the simple minus sign is used. The two dates may be entered in two cells say in B6 and B7 and wherever the difference is to appear, the formula is used. Here it would be “=B6-B7”. Let us say B6 is 17th February 2012 and B7 is 5th February 2012. The result displayed is “12”.
The autofill function works equally well with dates. Thus selecting B6 and B7, and dragging down, gives a series of dates with a gap of 12 days. For the basics of autofill, click here for an earlier post: http://computertipsforbeginners.blogspot.in/2011/05/excel-speed-up-data-entry.html
Some simple and interesting formulae on dates are: