Calculate a new period in CIS 300 April 04, 2025 15:02 Updated Hover over 'Companies' in the menu bar. Click 'CIS 300' on the drop down. Click 'Calculate new period' button. Select the number for the tax month from the drop down. Select the year for the tax year from the drop down. Click the 'Calculate' button. Related to CIS construction Related articles How to poll manually for messages