Hi,
A good point to start is with Civil 3D built-in reports source code, please take a look C:\ProgramData\Autodesk\C3D 2014\enu\Data\Reports\Net\Source
The report you showed, is it a custom report? I tried find more information on the back and ahead but it's not clear...maybe you/we can find out by looking at the alignment that was used to created this report.