> Looking at the table of PG's table, I have a question:
> is there a typo? "BP" instead of "BC" (in the case of PIA).
I suspect so, but Piotr will answer for himself.
The 'problem' with using 'before present' is that this is very real
dating system: BP is to be construed as 'before AD 1950'; 'years ago'
or 'y/a' is unambiguous, but you do need to check the date a statement
was actually made this way.