What are the " " and "-" Numbers under the Totals in the Analytics Summary?

You may have noticed figures that are either positive (+) or negative (-) under metrics in the Siteimprove Analytics tool.
The figures shown are comparisons of metrics (trend data). By default, Siteimprove compares the current period chosen with the previous period. This can be changed as needed.

In the screenshot above, you can see where this trend data is displayed in the Analytics Overview Summary.

Trend data will only appear when comparing with different periods, filters, or groups using the "compare to" dropdown. Metrics (e.g. visits, page views, bounce rate, etc.) are shown in graphs in the Overview Summary but do not provide trend data.

By clicking on the question mark next to the figures shown, you will be given more detailed information. In this example, Q3 has been selected to show both results and results compared to Q3 in the previous year. We can now see that visits have decreased by 981 visits, indicated by the (-) sign.