Any data for average number of papers per year at different career stages? Is there any data for the average number of papers published per year by individuals at different career stages (ph.d. student, postdoc, tenure-track, tenured associate/full professor)? It would obviously be dependent on research areas and I also realize that such data may not be easy to obtain - hence the question to put it out and hope to get some direction for my study. I am interested in data from the Computer Science and/or Applied Mathematics fields, but answers for other research areas could also be interesting. In absence of data, anecdotal experience in one's branch may also be helpful.

UPDATE: 
- Obviously, the number of paper per year is highly field specific. So is citation counts (which includes all the analysis it comes with such as average citation counts, h factors, impact factor of a journal and so on).
- Several countries such as the New Zealand, have their own research evaluation system in which one of the important evaluation criterion for research-groups or even individuals is the number of papers published in one to six years span. The data for average number of papers by individuals in different disciplines may put these evaluations in perspective with the global averages. e.g., individual publishing two paper per year in a sub branch where the average number of papers per year by individuals is one should not be directly compared to those publishing 10 papers a year in subbranches in which 15 papers per year is the average norm.
In short, the purpose of obtaining such data is to provide corrections to the evaluation systems in such countries.
Italy introduced a few years ago a habilitation process which involves heavy bibliometric evaluation, and in the process they computed median values for all the professors in Italian universities for:

number of papers published in 10 years
citations per year
a sort of normalized H-index: the number h such that the person has h papers with score &gt;=h, where a paper published Y years ago with C citations has score 4C/Y. (more precisely defined here (Italian) and here).

The medians are separate by discipline and academic role (associate and full professor only --- not for assistants, unfortunately). You can find them here: associate full, and a legend for the codes of the scientific disciplines is here. The documents are in Italian, but you can google-translate them (or guess the meaning of most words, it's not too difficult for an English speaker).
For instance, in computer science (01/B1) the medians for an associate professor are

10 journal papers / 10 years,
9.15 citations / year
&quot;contemporary H-index&quot; 5.

and for a full professor

12 papers / 10 years
14.8 citations / year
&quot;contemporary H-index&quot; 6.

The calculations are of course imperfect, but they are very interesting to browse and give an idea of how wildly these numbers vary across different fields. For instance, the typical professor in nuclear physics (02/A1) publishes 59.5 papers over 10 years and gets over 104 citations per year, while one in mathematical logic (01/A1) publishes 5 papers in 10 years and gets 1.74 citations per year.