Getting it inside of Netsuite without using analytics wouldn't really work without customization. We currently use a set of automation tools and cloud based BI tools to help in some of these cases, but we also use Analytics in NetSuite. Although there are limitations to SuiteAnalytics, your situation is a good fit for it because you can build our your report in SuiteAnalytics and then on the NetSuite Dashboard, add an analytics tile that displays the chart. Here's an example...