KMP -- the key is the numbers refer to point to point passengers traveling at business class fare
So for Boston Logan to London Heathrow - 18,574 passengers originated in Boston and terminated in London this doesn't count people who arrived via some flight to BOS and continued on by some flight from LHR. For example someone who started a journey in Burlington VT arriving at BOS by flying like a ping pong ball:
- 5:48am to 7:44am 1h 56m Burlington Intl. (BTV) to Ronald Reagan Washington National (DCA)
- Ronald Reagan Washington National (DCA) to Greater Rochester Intl. (ROC)
- 1:46pm to 3:09pm Greater Rochester Intl. (ROC) to Logan Intl. (BOS)
- and then boarding the overnight to LHR
- and then upon arrival in London continuing on to Lerwick [on Shetland Island] from LHR 6:50 AM Heathrow Airport LHR 8:25 AM Aberdeen Airport ABZ
- 10:30 AM Aberdeen Airport ABZ 11:30 AM Sumburgh Airport LSI Shetland Island
That flight doesn't count because the origin was BVT and the termination point was LSI
now of course if you arrived at BOS and spend the night in a hotel room and did the same in London before continuing -- then you would have had a BOS-- LHR flight and you would have counted
Or if you boarded a bus in Downtown Burlington VT for Boston South Station Bus Terminal then walked to the Silver Line and took SL1 from South Station to Terminal E then flew BOS - LHR then boarded a Train to Paddington Station followed by a Tube to Victoria Station then walk to the Victoria Bus Terminal board a bus to Aberdeen and then via a ferry to Shetland Island with a final bus to Lerwick -- might take a mite longer but it would count
Somewhat useless statistics