  We analyze a set of three databases at different levels of aggregation (i) a
database of approximately $10^6$ publications of 247 countries in the period
between 1980--2001. (ii) A database of 508 academic institutions from European
Union (EU) and 408 institutes from USA in the 11 year period between during
1991--2001. (iii) A database comprising of 2330 Flemish authors in the period
1980--2000. At all levels of aggregation we find that the mean annual growth
rates of publications is independent of the number of publications of the
various units involved. We also find that the standard deviation of the
distribution of annual growth rates decays with the number of publications as a
power law with exponent $\approx 0.3$. These findings are consistent with those
of recent studies of systems such as the size of R&D funding budgets of
countries, the research publication volumes of US universities, and the size of
business firms.
