The term 'COMMON LEVEL' can be broken down into three parts: PAR (3 letters), MON, and LEVEL. PAR stands for 'Proportional Area Reduction, ' which is a method of adjusting property values for tax purposes. MON refers to the fact that this adjustment is done on a consistent, or 'COMMON, ' basis. Finally, LEVEL indicates that the adjustment is done in order to maintain a certain LEVEL of fairness. In summary, COMMON LEVEL is a method of adjusting property values for tax purposes in a consistent manner in order to ensure fairness.