In the Annual Volume cell B$3,$ create a formula that adds the $$Sales Volume$$ for that model number from the $4$ previously created Q$1$ Actual, Q$2,$ Q$3$ & Q$4$ worksheets. Make sure that the values generated by this formula in this cell will automatically update if any of the input values are changed on any of the $4$ individual quarterly sheets at a later time. If you do this right, by changing a volume on the Q$1$ page then your awesome formula on this summary page will recognize the fact that you changed that cell and automatically recalculate your summary value! Copy this formula down for all of the models. The demonstration of how to do this is on the Module $1$ Level $3$ Part $2$ video.