We have formulated the problem of measuring the state of the electronic economy, and substantiated the necessity of using, at the system macro-level, the indicators that more accurately reflect the state of the electronic economy and its sectors. We have discussed the problem of low relative level of professional interest in the problems connected with electronic markets, electronic economy and infrastructure of electronic economy. A factor structure of indicators is proposed, which as a whole reflects the value of the latent category of the e-economy ecosystem. The electronic economy and its subsystem, electronic markets, is a new economic phenomenon whose state and dynamics are not described in most studies. This article attempts to define the terminology and factors that determine the state of the ecosystem of electronic markets, which include factors that reflect the quantitative and qualitative composition of participants in electronic markets, the financial subsystem of the electronic economy that ensures the movement of value in electronic markets. Based on certain factors, the comparative ranking models of countries from the point of view of the ecosystem of electronic markets and regression models can be constructed that allow estimating the size of electronic markets by the data on the state of their ecosystem. The results of the study presented in this article were obtained based on unofficial statistics offered by the analytical portal statista. Unofficial statistics was taken as a basis due to the lack of clear indicators of measurement in this sector of the economy, and also because of the lack of clear identification of this sector of the economy (electronic economy). As a rule, it is identified with the ICT sector of the economy, which makes it difficult to accurately measure it and is not entirely correct, since data and information are the end product for ICT organizations, and an intermediate one for e-business organizations, as for other (not ICT) sectors economy. The article raises the problem of identification of both theoretical and statistical electronic markets and the electronic economy as a whole. The application of the term ecosystem is proposed to reflect not only the metasystem of electronic markets, but also their subjects, as well as the interrelations between elements that reflect patterns.