Breww keeps a record of the total amount of beer produced in a calendar year. To see this figure, go to the Beer Duty tab and click Annual Estimate & settings. This will then show below your actual annual production volume for last year that you have entered (screenshot below).
To see total packaged volume, go to Reporting > Aggregate data report builder > Beer produced (Rackings) and select your parameters. Data from this report can be exported to Excel if desired.