Massive delete of rows, how to proceed?

[Arnau <arnaulist(at)andromeiberica(dot)com>]

Hi all,

  I have a table with statistics with more than 15 million rows. I'd
like to delete the oldest statistics and this can be about 7 million
rows. Which method would you recommend me to do this? I'd be also
interested in calculate some kind of statistics about these deleted
rows, like how many rows have been deleted for date. I was thinking in
creating a function, any recommendations?

Thank you very much
--
Arnau