Why can not excel my summation, Ji Jiji

My excel table set up in the summation formula used to be imported automatically appear after the number of total value, import value is the total value of the future must double-click the cell that become the total value of the total value of the new, but in other people's table Machine can be normal sum, I Kaodao inside the machine can not be a!

point tools – options – to re-calculation – automatically re-election counting to determine, click f9, will be able to, Sometimes this happens excle table is too large, leading to slow the calculation.Select your requirements and data, and then right-click the file EXCEL in the lower right corner of the “digital” and select the sum would be enough!