Can Comparisons of income can be very difficult for two companies even though they sell the same products in equal volume?

There are many different methods of financial reporting accepted by the accounting profession as promulgated by the Financial Accounting Standards Board. Though the industry has continually tried to provide uniform guidelines, and procedures, many options remain open to the reporting firm. Every item on the income statement and balance sheet must be given careful attention. Two apparently similar firms may show different values for sales, research, and development, extraordinary losses, and many other items.