Purpose – An intertemporal comparison of the value created by Intellectual capital cannot disregard the current prices realized on the market by individual companies, because, at the corporate level, a decrease in sales prices results in a decrease of the value created (Zappa, 1919; 1920–1929). On the contrary, in comparisons in constant prices, this decrease is not measured at macroeconomic level (Weil, 2007; OECD, 2001). The goal of this paper is to examine the different measures of the Value Added created by Intellectual capital at micro and macroeconomic level and the relationship between these measures and the Neoclassical Theory of Subjective Value (Menger, 1976; Robbins, 1945; Wieser, 1889–2006; Wicksell, 1898–2006; Fisher, 1892; 1911–2006). Design/methodology/approach – We present the theoretical and practical limits of the use of index numbers to express the value created in constant prices even in international comparisons (Fisher, 1911–2006). As stated by the Theory of the Subjective Value any quantity of the same good has a different value as a function of marginal utility (Marshall, 1890–2006); so the deflating by means of a price index, distorts the value attributed by the market at micro economic level to different goods. In this way, comparison to constant prices also modifies relative prices. Originality/value – The valuation at current prices implies a different theory of the value of goods and we have identified a Third Generation of Marginalism in Friedrich von Wieser, Knut Wicksell and Irving Fisher since they indicate the difference between subjective and objective value. Intertemporal comparison at macroeconomic level is conducted deflating value so to consider the variation of the purchasing power of money (ISTAT, 2011). But the separation of changes in quantity from changes in price implies several problems (Fisher, 1911–2006) and we use modified input-output analysis to quantify in current prices the Value Added and the production realized in the economic system. Practical implications – The international and intertemporal comparisons made by governments and by the statistical institutes via National Accountings, should be at current prices and at purchasing power parity, i.e. excluding the use of index numbers to deflate changes in production. The comparison at current prices would result in assessments of the contributions provided by the intellectual capital (VAIC) differ from those measured in constant prices and without indicating the net asset of the economic systems (GDP). It is therefore necessary that the comparison measures not only indicate the statistical model, but also the economic theory of reference.