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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.

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    I don't think this is possible out of the box in a single layer. The symbology is set by the values in the entire layer, not each individual record's values. You'd have to normalize your data ranges to a constant scale. And without normalization, it might be confusing to look at red on one map and it be 10, while the next page it means 1000. This is one reason choropleths are better suited to proportional rather than quantity data. It might be helpful to post a screenshot of your data or describe it in more detail. It sounds like you have sub-regions with a particular value in a county? – Chris W Nov 19 '14 at 0:11
  • These maps are meant to be viewed independent of one another. The data driven pages are intended to make the process of creating over 100 maps a lot faster and more uniform. – AlexC Nov 19 '14 at 14:40
  • I tried to add a screenshot, but couldn't get the image to load. Yes, there are several subregions (often thousands) within each county. – AlexC Nov 19 '14 at 15:00
  • Unfortunately I think the only to use DDP is to have a separate layer for each county so each could be symbolized to its own classification range. That, or as I said, normalize the data to a common scale such as x per square mile, or just high/med/low etc. Without knowing what the data is about, it's hard to suggest. As for including an image, you should just have to click the picture button at the top of the edit window and browse to the file on your computer - it will upload and host here. If you have it hosted elsewhere, you can load from there too, or post a link and we can edit for you. – Chris W Nov 19 '14 at 19:38
  • What about adding an attribute (call it ScaleMax or something) to the county feature class that would specify the top of the scale? Since the scale is in 4 parts, you might be able to finagle the DDP to use that to generate the legend. If the DDP won't do that for you, you could hack together a quick tool in ModelBuilder that would fix the legend based on that same attribute. Also, your ranges wouldn't be 1-10, 10-20, etc. They'd be 0-9, 10-19, etc. – P.T. Curran Jul 6 '17 at 18:48

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