The application of Samuelson's theorem on value invariance to the case of intertemporally optimizing "rms is shown to require a judiciously chosen economic depreciation formula which depends on both current stock and current #ow variables, in order to prevent the "rms from changing their actions in the face of the tax regime. We illustrate by deriving depreciation rules which achieve non-distor...

Because unanticipated monetary expansion leads to real exchange rate depreciation, and because the harms of real depreciation are greater in more open economies, the benefits of unanticipated expansion are decreasing in the degree of openness. Models in which the absence of precommitment in monetary policy leads to excessive inflation therefore predict lower average inflation in more open econo...

• EBITDA increased 23% in real terms during the third quarter to Ps.4.463 billion. In dollar terms, EBITDA grew 34% to US$477 million during the third quarter as compared to US$355 million during the same period a year ago. EBITDA, with respect to the CEMEX Group, equals operating income before amortization expense plus depreciation. Amortization of goodwill is not included in operating income,...