I think this is pretty minor, but ran across it yesterday.
If you are comparing two date ranges, the trend line labels don't reflect the dates the data is for. I think they always use the date for the entire report.
In the example attached, I'm comparing This Month vs. Last Month. In both cases, the label under the chart shows March 1 - March 31 when the chart is really showing February 1 - March 31.
