If you are in v4.2, you must be in the view tab. Then right click on the bar graph and select "properties." When the properties window pops up, you will see tabs at the top. Select the "axis" tab. Then at the top, you will see the heading "scale" and under that, you will see the radio buttons, "fixed" and "automatic". Select the "fixed" radio button and then you can type in the values (min, max, tick mark increments, etc.) you want to appear along the Y axis.