The Wikimedia pageviews complete dumps include not only the daily pageviews but also the monthly pageviews in a bz2 file (for instance these are the pageviews for the month of June by human users, spiders and automated users: https://dumps.wikimedia.org/other/pageview_complete/monthly/2021/2021-06/). However, it is not possible to decompressed these files, while there is no problem with the daily bz2 files.

For instance, in Ubuntu 21.04, when executing the command bzip2 -dk pageviews-202106-user.bz2, it returns the following error: is not a bzip2 file.