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Bar chart display

February 02 2010 | 1 comment
Categories: Map Elements

I am using a bar chart with 2 data fields to display data on my map. In the legend, I have my 2 data fields displayed, and there is a random number (not sure if it is a mean or median of one of my data columns) which is also displayed in the legend, and I cannot remove it. I'd like to remove this random number from the legend.

Can anyone help? Picture is attached. The "4.4" should not be there.

Mapping Center Answer:

Since you do not want to display the number next to the bar, you should probably also eliminate the bar from your legend -- otherwise people will wonder what it is and it won't have a label to describe it. So here is how you can do that…

…after you have inserted the legend, right click it to see its properties. Then on the Items tab, in the Legend Items right pane at the top right, right click they legend item used to make this legend, click Properties and click the General tab. At the bottom is a drop down arrow next to "Only show classes from this heading". You will probably see three options: "All" and two "all other values". The first "all other values" relates to the legend patches and their labels (% illness in spring and autumn, for your map), and the second "all other values" relates to the example bar chart and its label (4.4 on your map.) Click the second and click OK to accept all the changes.

This should take care of the problem for you!

What the number means posted by Aileen Buckley on Feb 2 2010 1:18PM
By the way, in case you were wondering, about the number value next to the example chart that is created automatically when you insert the legend, it is not the mean or the median value. Rather, it represents the attribute value for a chart symbol of that size on the map. For your map, that means it represents a value of 4.4% illness.

The following link from the ArcGIS Online Help relates to this:

About symbolizing data to represent quantity

http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?id=292&pid=286&topicname=About_symbolizing_data_to_represent_quantity

"When you symbolize a layer with charts, a chart symbol and a number are placed in the table of contents under the layer's name. The number next to the chart symbol represents the attribute value for a chart symbol of that size on the map. For example, a value of five means a chart on the map that is the same size as the chart in the table of contents represents 5 data units. Similarly, a chart on the map that is twice as big as the chart in the table of contents represents 10 data units. The chart symbol and value in the table of contents also appear in the legend.
For bar/column charts, the value refers to the highest bar in the bar/column chart symbol. With stacked or pie charts, it refers to the sum of all fields being represented by the stacked or pie chart symbol."

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