public class JobStatistics 

{
  var query = new JobStatisticsQuery()
  {
    // Search for open jobs assigned to users
    Q = "\"assignedType='User' AND closed=0 \""
  };
  var jobManager = WorkflowClientModule.JobsManager;
  var results = jobManager.CalculateJobStatistics(query);
  var totalJobs = results.Total;
}