The media has widely reported the record-breaking 568,061 passengers on BART and 88,000 Caltrain passengers on the day of the San Francisco Giants parade. Just how do they count these people?
BART counts the number of people who exit a station through the fare gates. You insert your magnetic stripe paper ticket into the gate or slide your Clipper card over it and the gate magically swooshes open, making passenger counts super easy for BART. All entry and exits into and out of a BART station are through these fare gates.
You’ll see passengers who make a round trip are counted twice, but this is apparently standard operating procedure for any transportation conveyance, including highway traffic counts.
Caltrain does not restrict platform access in any way. Tickets are checked after boarding by conductors, so Caltrain’s record breaking 88,000 passengers on October 31 is arrived at by estimation. They count the number of one way and round trip tickets that were purchased along with 8 ride tags. From that they add a fudge factor of monthly pass holders. They can make a reasonable guess of monthly pass passengers from their February passenger count.
On top of that, they had people at 4th & King in San Francisco to count the passengers boarding and debarking the trains. Plug all of that in, and they come up with 88,000 rides for Wednesday, October 31, 2012. This beats the old record of 80,000 rides that occurred at the previous Giants Parade day in 2010 by 10%. Caltrain carries about 50,000 passengers on a normal workday.
Bay Area toll bridge authorities reported about 5% less traffic than usual on the parade day. Golden Gate Bridge District reports about 12,000 ferry trips from and to Sausalito and Larkspur, not quite matching the 13,000 rides in 2010.