I am creating choropleth maps for quantified data. Each DDP will focus on a new county, which is shown by using a clip of the data frame (by the county boundary). I want to define quantified legend symbology by equal intervals, which will change for each DDP. This means that the legend's intervals would change for each page. For example, Montgomery county may have a data range of 0-20, therefore the legend's intervals would be 0-10, 10-20, 20-30, and 30-40. Bucks County may have a data range of 0-400, therefore the legend's intervals would be 0-100, 100-200, 200-300, and 300-400.