Running engagement pulse checks in Teams, how do you track trends over time?

Forms is fine for collecting a quick pulse, but this is where it starts to show its limits for engagement work. You can absolutely build the trend piece yourself with Excel or Power BI, but then somebody has to keep consolidating the results every month and make sure the questions/columns stay consistent. If you want to stay completely native to M365, I’d probably push the Forms responses into a single SharePoint list or dataset rather than treating every pulse as a separate file. Then Power BI can sit on top of that and show the same questions over time.

With that said, if you are serious about your surveys, I definitely recommend finding a dedicated survey tool and not just forms. There are great ones that integrate with MS Teams like Teamflect, Matter, or even Viva Pulse for that matter. 

For a team of 20, I wouldn’t overengineer it though. If Forms is otherwise working for you, centralizing the data is probably the first thing I’d fix.

Your reporting problem comes from creating a new Form each month, which leaves each pulse in a separate response set. For a lightweight Forms approach, reuse one form, keep the rating questions and scales unchanged, and add a required reporting-period question such as Month. Create the form from Teams, SharePoint, OneDrive, or Excel for the web so responses remain linked to one Excel workbook. Build a PivotTable and chart from that table, using Month as the column dimension and each rating question as a value; future responses then extend the same dataset. Keep one team link and open or close the form only during each collection window. If your organization licenses Viva Pulse, it better fits recurring engagement checks: schedule or resend the same Pulse and preserve the questions so its report generates trend views. With only 20 staff, verify the minimum-response threshold before relying on Viva Pulse reporting.