Remember that if you calculate periods out of order this can cause inaccurate results.
It is best practice to NEVER CALCULATE A PRIOR PERIOD if possible. There may have been changes in your current system that could impact the prior periods. The system will not alert you of changes between your initial calculation and the second time you calc. Any time you run into a prior period issue we recommend putting the adjustment in the current period. If you have further questions remember you can always contact Support.