Absolutely possible in both the new and old report writer. If using the web reports you have the benefits of a simpler method of just including all three data sources into one report- not merging the results. This will be easier as merging the results will likely require a SQL query.
I guess I should add that currently the 3 reports are written in Report Writer & not in the Web Reports.
Can those still be used as data sources for a Web-based report or would I need to rewrite those 3 reports into a new Web-based report?
You would need to remake the reports in the web report writer, but it's a heck of a lot simpler than it sounds
I would mention that you should check your data retention levels. By default, statistics between 7-30 days back are hourly averages; so you might not be getting accurate numbers with your reports at the moment.
If you need more help, feel free to ask!
Loop1 Systems: SolarWinds Training and Professional Services
Can you please share your report here for understanding purpose, please?
If these are all in Report Writer, you can try this...
1. Extract the SQL from each
a. Open the Report
b. Click Report at the top
c. Select "Show SQL"
d. Copy all
2.Paste that SQL query into a new Custom Table report element in a new report.
3. Repeat for the other reports
NOTE - you may need to adjust some of the date parameters so that the tables show what you want for the time frames you want.