Per Vehicles

[Dave Wilton]

This is probably just a typo and not a linguistic trend, but I noted today
that one sign on the carpool lane of highway I-880 South in Fremont, CA
reads:

"Carpool is 2 persons per vehicles."

All the other signs I have seen (including the sign on the opposite side
facing I-880 North) use the singular "vehicle". What's really odd is that I
assume these signs are made in batches, but this appears to be the only one
with the plural "vehicles." Perhaps there are some others scattered across
California. The sign is identical to the others, with the exception of the
plural.

--Dave Wilton
  dave at wilton.net
  http://www.wilton.net