using inc_performance type=7 gives duplicate rows

Summary:

When adding the first closed date from the inc_perf table to my report, I get two rows for every solved incident, one with a closed date and one with no closed date.

Content (please ensure you mask any confidential information):

I have a report with about 150 columns most of which are from the incidents table and a custom object. It was working fine. When I realized that the Date Closed column from the incidents table only shows the latest date it was closed, that was not the date the users needed. I changed the incidents.date_closed column to a column with if(inc_performance.intv_type = 7, inc_performance.time_end) . It displays the dates I want just fine. But for some reason now I have 2 rows for every solved incident, one with a closed date, and one with no date in