This metric compares how the market values a company against its accounting book value. A ratio below one indicates the market values the company lower than its balance sheet equity.
This situation can be interpreted in two ways. Either the stock is undervalued, or investors doubt that the recorded assets will generate returns and expect their depreciation. Return on equity helps distinguish between these interpretations: persistently low capital returns usually explain the low valuation.
Applicability depends on business type. The metric is informative for banks and companies with significant tangible assets, where book value approximates economic value. It works poorly for businesses whose value lies in brand, technology, or customer base—these assets typically aren't reflected on the balance sheet, so a high ratio doesn't indicate overvaluation.
Additional limitation: book value depends on accounting policies and the timing of asset revaluation, so comparisons require consistent reporting standards.