I did a video to show the trapazoid fit process in action. I was able to compensate for Google's processing somewhat but not entirely. Excel recalculates the worksheet if a cell's content is changed to moving a cell about is an easy way to recalculate the worksheet. Each time the selected box is moved the worksheet computes 1000 random trapazoidal numbers, does the data analysis and computes a fit for the data.
You can pause the video to study a particular fit. It helps to zoom in a little too.