cfchart ignores my scalefrom value

Hi all,
 
  I have the following codes in my page.
 
  The style variable holds the custom style. 
  
  <cfchart chartheight="450" chartwidth="550" gridlines="9"
  yaxistitle="Score" scalefrom="20" scaleto="100" style="#style#"
  format="png" >
      
  <cfchartseries query="variables.chart_query" type="scatter"
  seriescolor="##000000" itemcolumn="MyItem" valuecolumn="MyScore"/>
  
  </cfchart>

Before I begin, please go to http://www.monteandjanicechan.com/chart_good.jpg.  This is how I want my report to come up.  On the x-axis, there will always be three items as long as at least one of them has values.  If an item does not have any values (i.e. 2010), there would not be a marker in the chart.

The problem occurs only when only one item has value.  Please see http://www.monteandjanicechan.com/chart_bad.jpg.  As you can see, 2008 and 2010 do not have any values; y-axis is now scaled from 0 to 100.  I have tried setting one of the items (ex. 2008) a value of 0 or something off the chart; it would scale according to this off-the-chart value and the 2009 value.  In short, I have to have at least two items with values between 20 and 100 in order for cfchart to scale from 20 to 100.

My question is, how can I correct the issue so that cfchart would ALWAYS scale from 20 to 100?  I am running CF9.

Thanks in advance,
Monte