This may be an easy question, or it may not be possible!

Could someone please offer some help as I am new to VBA and cannot work this out using normal excel functions.

I have a spreadsheet with some fields containing time spent on a project by members of staff. At the end of the row there is a total of all the time spent. Each week when I input the time, I have to record the amount of time already in the cell, then use a calculator (or my head!) to add the new time to it then input this new time, which is again then totalled at the end of the row.

Is there any way of keeping a running total? what I mean is that a cell would total what is input into another cell along with what was previously in the cell and remember what was in the total, to total a new total!-does anyone understand what I mean by this?!