What is true about common size statements of a company?

It expresses all items of a financial statement as a percentage of some common base such as revenue from operations for statement of profit and loss and total assets for balance sheet.

Common Size Statements are the statements which indicate the relationship of different items of a financial statement with a common item by expressing each item as a percentage of that common item. The percentage thus calculated can be easily compared with the results of corresponding percentages of the previous year or of some other firms, as the numbers are brought to common base. This analysis is also known as ‘Vertical analysis’. Comparative statement shows changes in all items of financial statements in absolute and percentage terms over a period of time for a firm or between two firms.