The trend editor's Parameters tab lets you further refine the query results in terms of row limits, time zone restraints, filters, and start and end times. If you set parameters in the base query used by this trend, those parameters appear on the Trend Parameters tab. In the trend, you can specify default parameters.
At Report building time, you can opt to run the report with the default parameters or “all parameters.” You can also further refine parameter details for a specific run of a report. For more information on specifying parameters in reports, see Setting Default and Custom Report Parameters.
Note: Trend start/end times and row limits are used for gathering the data, and overwrite the start/end times and row limits set in the base query. If you do not customize the Trend Parameters, the defaults on this tab are used (not the start/end times and row limit on the Query General Attributes tab).
For reporting on the data after the trend has collected it, you can set new start/end times and row limit in the Report Parameters tab. The report parameters prescribe only the “outbound” or publishing data derived from the data already collected, not how the data is gathered.