How to Insert a Trendline

  1. Highlight the data you want to by clicking on it in the plot

  2. Select 'Trendline' in the 'Insert' menu.

  3. Pick the 'linear' trend. Go to the 'Options' window and click 'Display equation on Chart'. Then hit the 'ok' button.

The rate of change is the slope of the straight line that appeared in the graph. The displayed equation gives you this slope (y=slope*x+intercept).