I often see claims that new (generally government) projects will "create n jobs".
For example, this 2013 claim from the Economic Development Blog about the 2020 Olympic Games:
The Olympic Games are expected to create 152,000 jobs nationwide across Japan. This includes 84,000 new jobs in Tokyo and 68,000 in the rest of the country.
I have always found such claims to be vapid, because it doesn't say how long the jobs last.
Sticking to the example: One of those new positions might be to be a security guard for a month during the games. One of those new positions might be to work on the planning for the event for seven years. One of those new positions might be to be a groundskeeper at a new Olympic facility for decades.
Lumping these together seems like it is a misleading metric. Perhaps saying "250,000 job-months" would be a better measure?
But I am economically naive. Perhaps economists have already considered this and have a standard definition I don't know about to allow them to properly compare.
Are these figures mostly meaningless, just being used to hype a project by its proponents? Are they accepted estimates of real economic boost a project might bring?