I was on the Circle line train to work and I saw one of the adverts for the London Underground that said that they now have over 1 billion passengers a year. Now that is a lot of passengers and that is their explanation for the problems with service as upgrades are needed to cope with this unexpected capacity.
But 1 billions passengers that really is a lot. That is nearly 1 in 6 of the world's population. That means that sometime during each year 1 in 6 of the people of the world decide to come to the UK and use the Tube. That is a lot of foreign visitors, South Americans, Americans, Canadians, Africans, Chinese etc. That is an average of about 2.8 million people per day arriving in London and using the Tube or 5,000 Jumbo Jet loads across the two main airports and the smaller airports a plane load landing every 20 seconds, 24 hours a day seven days a week.
Do I think each of these "people" is an individual? Do I think that even 1/6 of the people of the UK use the tube every year? The second answer is a possible yes as London and the South East are a huge part of the UK population but how do you count individuals and not repeats? As for 1 billion individuals from across the world I doubt this given the number of people who don't even own a passport and do not have the financial possibility of travelling to the UK. So what it says is not what it means. It probably means 1 billion passenger days - users are counted as individual for each day they use the tube. It is probably too small to mean passenger journeys as there are many small journeys and people go back and forward and is that one journey or two? Anyway the point is there is a misleading difference between the numbers we say and what they actually mean. They are very rarely easily counted.