Open the Excel 2010 file where you graph is located. Once the sheet opens, click on your graph to select it. Click the "Layout" tab at the top of the window, then click the "Axes" button in the ...

In this graph the intervals on the bottom axis are unequal, making it difficult to read. Scales should either start at zero, or be concertinaed (squashed) as shown in the y-axis in the above graph.