For every variable KPI, we'll automatically show a comparison of that same metric from the previous period. The previous period will update right along with any date range customizations you set on your dashboard. For example, if you choose to set your dashboard's date range to Monthly, the previous period comparison for each KPI will compare the current 30 days of data to the previous 30 days of data. Then, if you switch to another date range, Rilo will automatically adjust the previous period to match. That way, you're always comparing apples to apples.