I am trying to come up with an equation. Here is what I am trying to do. I am trying to get a running total by multiplying a monthly rate for renting something that will at all times keep a running total at all times. Monthly rate x month started = Running total. Keep in mind there doesn't need to be a total based on the number of days owned on a month (Not to be pro-rated in other words.) Something like if it cost $100 a month in January. Then by July 1st you would owe $600. On June 15th for example you would still only owe $500 because the month hasn't ended. In other words the running total would only show completed month totals. Maybe I don't have the best knowledge of excel but I am ok at the equations. The problem is from using months instead of simply multiplying numbers. Any help would be appreciated. Thanks.