In reports, we've currently only got the last 7 days as a date range option at widget level. It would be really handy to also have the last 30 days and last 90 days.
The issue at the moment is that when you compare a date range, such as this month or this quarter, against the previous period, it compares against the full previous month or quarter rather than the equivalent period up to today's date. This means you're comparing different lengths of time, so the percentage increase or decrease isn't accurate.
Having last 30 days and last 90 days as options would make it much easier to compare performance over equivalent periods.