You can customize the queries you use to recall historical data, and your custom queries should return two arrays:

• _scfw.historical_statistics.causes – Causes stores the list of historical selected causes for the current troubleshooter. The score is the number of times each cause has been selected.
   
• _scfw.historical_statistics.observations – Observations stores the list of observations per cause for the current troubleshooter. The score is the accumulated weight of each observation.