Capital in the Twenty-First Century, Thomas Piketty (Parte II)

En la primera parte, utilicé algunos extractos del libro de Thomas Piketty para destacar algunas ideas relevantes a la hora de decidir si el impuesto de sucesiones debe o no ser utilizado. En esta segunda parte destacaré un extracto del mismo libro que sirve para entender el funcionamiento del Ratio Q de Tobin (de James Tobin).

Según el ratio de James Tobin, utilizado básicamente para las sociedades cotizadas, el valor de mercado del total de las compañías dividido entre el valor total de los activos contables debe tender a 1. Esto se debe a que si el valor es superior a 1 significará que la compañía está sobrevalorada, mientras que si el valor es inferior a 1 infravalorada. Es decir, si es superior a 1 sería más económico crear una empresa igual desde cero, mientras que al contrario sería más rentable adquirir la compañía ya constituida. Valga decir, que es más fácil entender que el Ratio Q sea mayor o menor a 1 cuando observamos una única compañía, mientras que es más complejo entender este fenómeno cuando el conjunto de las compañías de un país tiene un Ratio Q claramente superior o inferior a 1.

Este ratio no puede tomarse como una verdad absoluta ni darle demasiado peso a la hora de decidir si invertir o no en una compañía, pues la Ratio Q fluctúa debido a la incertidumbre respecto al futuro de la compañía. Debido a la incertidumbre del mercado puede ocurrir, y así ocurre, que durante años el ratio Q de las compañías de un país se mantengan por encima de 1 o al revés. Sin embargo, cuando este ratio se incrementa de forma continua durante varios años seguidos puede ser una buena señal de que el mercado está sufriendo una burbuja. Este hecho se observó con la burbuja de Internet en 2001 y 2002 y con la burbuja inmobiliaria de 2007 y 2008.

Piketty utiliza el Ratio Q para mostrar el repunte del valor  de los activos durante las últimas décadas y el incremento del ratio capital/ingresos. Al respecto explica:

In theory, in the absence of all uncertainty, the market value and book value of a firm should be the same, and the ratio of the two should therefore be equal to 1 (or 100 percent). This is normally the case when a company is created. (…)

The difficulty arises from the fact that anticipating the future of the firm quickly becomes more complex and uncertain. After a certain time, for example, no one is really sure whether the investment of 50 million euros several years earlier is really economically useful to the firm. The book value may then diverge from the market value. (…) The market value of the firm, that is, its stock market capitalization, may be significantly lower or higher, depending on whether financial markets have suddenly become more optimistic or pessimistic about the firm’s ability to use its investments to generate new business and profits. That is why, in practice, one always observes enormous variations in the ratio of the market value to the book value of individual firms. (…)

It is more difficult to understand why Tobin’s Q, when measured for all firms in a given country taken together, should be systematically greater or smaller than 1. Classically, two explanations have been given.

If certain immaterial investments (…) are not counted on the balance sheet, then it is logical for the market value to be structurally greater than the book value. (…) But these ratios greater than 1 also reflect stock market bubbles in both countries. (…)

Conversely, if the stockholders of a company do not have full control, say, because they have to compromise in a long-term relationship with other “stakeholders” (…), then it is logical that the market value should be structurally less than the book value. This may explain the ratios slightly below one observed in France (around 80 percent) and especially Germany and Japan (around 50-70 percent) in the 1990s and 2000s, when English and US firms were at or above 100 percent (…). Note, too, that stock market capitalization is calculated on the basis of prices observed in current stock transactions, which generally correspond to buyers seeking to take control of the firm. In the latter case, it is common to pay a price significantly higher than the current market price, typically on the order of 20 percent higher. This difference may e enough to explain a Tobin’s Q of around 80 percent, even when there are no stakeholders other than minority shareholders.