One or even several ratios might be misleading, but when combined with other knowledge of a company's management and economic circumstances, ratio analysis can tell much about a corporation. Second, there is no single correct value for a ratio. The observation that the value of a particular ratio is too high, too low, or just right depends on the perspective of the analyst and on the company's competitive strategy. Third, a financial ratio is meaningful only when it is compared with some standard, such as an industry trend, ratio trend, a ratio trend for the specific company being analyzed, or a stated management objective. In trend analysis , ratios are compared over time, typically years.
Trend analysis works best with three to five years of ratios.
The second type of ratio analysis, cross-sectional analysis , compares the ratios of two or more companies in similar lines of business. One of the most popular forms of cross-sectional analysis compares a company's ratios to industry averages. These averages are developed by statistical services and trade associations and are updated annually. Some of these sources will be covered later in this guide. Financial ratios can also give mixed signals about a company's financial health, and can vary significantly among companies, industries, and over time.