Comparative Financial Statement means a comparative study of the items of Balance Sheet and Statement of P&l for two or more years. 

Note; When a Comparative Statement of same firm's Financial statement of two consecutive years, is known as Intra firm Comparison. It involves only a company.  
 
Note: When a Comparative Statement of the firm's financial statement is prepared with an other firm's financial statement, is known as Inter firm Comparison. It involves two or more different companies. 


 Common size statement express all items of financial statement as a percentage % basis. Such percentage is calculate on the basis of revenue from operation for Statement of P&l and total Asset for Balance Sheet.