Brazilian universities and rankings: What is going on?

Brazilian universities as a whole are performing badly in most international rankings. Although there is criticism about the methodological validity of rankings, it is a fact that there are too few Brazilian universities in the top and their positions are falling. There are no Brazilian universities among the top 100 of any international ranking. There are no more than 6 Brazilian universities in the top 500 of the research intensive Shanghai (ARWU) ranking. Moreover, the positions of the top Brazilian universities fell in the last edition of the Times Higher Education Emerging Economies ranking. A similar situation is found in the QS ranking.
What are the reasons for the bad performance? Why are Brazilian universities becoming worse?
A careful analysis of the parameters employed by the rankings may help us to find the answers. The main conclusions are that several well-entrenched practices that are peculiar to the Brazilian system may be part of the answer. In fact Brazilian universities did not get worse. They are stagnant. However, universities from other emerging countries are much more dynamic to respond to new demands and consistently improve their positions in the rankings.
Brazilian university authorities must face the challenge of making their universities more up-to-date with current best higher education practices if they really want to be in the top.