Hi Issah...
to do this, you will have to either use a memory table or strictly limit what functionality are available in your file/query table....
In a memory table, you just have to calculate the running total and add it as you add your lines...
In a file table, you would have to calculate/add the running total when you DISPLAY the line, and the problem is of course that records are read only when a line needs to be displayed, so if you allow the SEARCH function in your table, the user will arrive on a record without reading the previous ones, and you won't be able to calculate your total...
Same problem with the sort capabilities (but that is true also in a memory table,where yowould have to recalculate the total for each sort)
Best regards