How to edit the Vertical and Horizontal Axis on Charts

Hello Members,

I have an Excel table with two columns namely Items and Quantity. With the data in these 2 columns I have inserted a column chart on the same worksheet. The chart has Quantity on the Vertical axis and Items on the Horizontal axis. The charts appears fine to me. You can also have a look at the table data and the chart in the attached spreadsheet below.

Q: Now, The Vertical axis shows the values starting from 10 to 80 in intervals of 10 each. Now I would like to edit the range of values starting from 20 to 80 with the intervals of 20 each. I mean Vertical axis should show 20, 40, 60 and 80. Please let me know the steps to get this.