A Common Size Financial Statement is a financial statement in which each line is expressed as a percentage of the total. In a common size financial statement, each line item on the income statement is expressed as a percentage of sales whilst on the statement of financial statement each line item is expressed as a percentage of total assets. Common size financial statements are used as a tool for the analysis of the performance of business for example historical analysis. It also facilities analysis of how a business is performing in relation to an industry and also to compare the performance of the business among the main competitors.