Scheduled Job Count vs Actual Job Count SQL / Schema

Under the canned reports in  Backup > Scheduled Jobs > Job Details Scheduled vs Actual, does anybody have any idea on how the 2 columns, "Scheduled Job Count" and "Actual Job Count" are generated?  (Where do I look to find these in the schema, or how do you think the sql is being written to generate these?).  I'd like to generate these two columns, but in my own custom query report.

thanks