If you had a 1:1 of row:incidentnumber you can use the other suggestion for creating a formula field to make an "if field=true then 1 else 0" and then SUM that. the SUM can go in a header (unlike a RT).
If not you would need to have a way to count in your source data like creating a stored procedure
or
use a sub report
or
possibly a Graph or Crosstab.
Any of those work for you?
Edited by DBlank - 30 Sep 2009 at 12:21pm