Interval Type

Joinpoint allows users to customize the interval of their Independent Variable.   By clicking the “Interval Type” drop-down box on the Input File Tab, users can select an interval of “Annual”, “Monthly”, “Daily”, or “Other”.  When “Other” is selected, a custom interval name can be entered in the “Other Interval Name” box.  The custom name must be 40 characters or less.

Changing the Independent Variable interval will affect the names of some trends statistics produced by Joinpoint.  For instance, when the interval is set to “Annual”, Joinpoint will generate values called “Annual Percent Change (APC)“ and “Average Annual Percent Change (AAPC)”.  If the interval is changed to “Monthly” these values become “Monthly Percent Change (MPC)” and “Average Monthly Percent Change (AMPC)”.  When using a custom interval, such as “Quarterly”, the values become “Quarterly Percent Change (QPC)” and “Average Quarterly Percent Change”.