When using the Reports function in Change 5.2, the value of NULL shows up in the label of the graph for Trend Analysis with Value Breakdown.
The null word shows in the graph.
This issue was identified as a product defect under APAR PM62150.
The defect is because the report application needs a new version of BIRT to resolve it (version 2.3.1). The inclusion of the fix can only be done at a full version release.
The defect is reported here:
IBM Rational Change Report Builder
Diagnosing the problem
The null value shows up in the Trend Analysis with Value Breakdown graph.
Resolving the problem
Requires running multiple reports to work around this issue.