This is working as designed.
In CA Clarity PPM v13.x and v14.1, the RPT_CALENDAR table is populated by the 'Update Business Objects Table' job.
In CA PPM v14.2, the RPT_CALENDAR table is populated by the 'Load Data Warehouse' job.
This job is coded to populate approximately a 10 year period, beginning with Jan 1st, 5 years prior to the current year. For example, if the current year is 2015, the population of data will begin on January 1, 2010 and populate for 3650 days from this date; therefore ending just a few days full of a complete 10 year period for daily values. It will populate 520 Weeks, 120 Months, and 40 Quarters. The FTE data values are computed based on the Availability Slice Data present for the application 'admin' user configuration for the date ranges in this job.
To request an enhancement to change the way this function behaves, you can add an idea on the CA Communities site.
For v14.2, To learn more about Jaspersoft reporting and the Data Warehouse, reference the CA PPM Advanced Reporting and Database Schema Index.