I would like to import survey data captured outside of Checkbox and use external constants to produce analysis.

1. I have conducted a survey using Checkbox, but due to voluntary network security constraints, some of those surveyed could not access the server Checkbox and their data was captured "off-line". I need to bring that data into Checkbox so that I can create aggregate analysis over both collections. I know that I can export Checkbox data and merge it with this external data but then I can't use Checkbox reporting.

2. Not all the data I need for analysis can be derived from the captured data. E.g. I need to publish what the take-up was as a percentage of all those who were eligable to take the survey. Even if I get an answer that works for item 1 above, it still doesn't give me what I need. Somehow I need to report the percentage of those who could vote (not captured anywhere) who did vote (captured in Checkbox).