Direct mail ROI dashboard questions

Hi everyone,
 
I’m working on a dashboard to report direct mail ROI and need help creating two widgets (both of which I’m not sure are possible but sure hope so). Any help anyone can suggest would be greatly appreciated!
 
#1: percent of mail list responding to offer
I would love to create a widget that shows the % of people on a specific mail list who responded to the offer. I’ve managed to create the separate widgets for number of people mailed and number of people on the mail list who bought tickets within 2 weeks of receiving our mailer (see screenshot below), but I can’t figure out how to combine them for an actual %.
 
Is there a formula I can create that would divide the number of constituent IDs that have ordered tickets by the total number of people in a specific list? I can do this easily manually, of course, but it would be nice to have the number automatically show up if I share the report with colleagues.
 
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#2: Cumulative Sales 2 weeks before and 2 weeks after mail date
I’m trying to create a bar chart that shows only two bars, each of which represents total cumulative revenue within a specific 2-week span. I can’t figure out how to build two bars that show total sales within custom date ranges, however…the whole chart just goes blank if I try. My current workaround is to split the widget into weekly reports (screenshot below), but it’s harder to see the overall trend if a 14-day span covers three calendar weeks.
 
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Anh Le | Director of Marketing & PR
Opera Theatre of Saint Louis | ExperienceOpera.org
ale@opera-stl.org | (314) 963-4294
 
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