The International Olympic Committee has narrowed down the bidders to host the 2020 Summer Olympics from five to three, eliminating Baku, Azerbaijan and Doha, Qatar, in favor of Tokyo, Madrid and Istanbul.

Japan's stake in the games may be higher than its competitors: Tokyo 2020 bid chief Tsunekazu Takeda said on Thursday that hosting the games would lift the spirits of and give big, big power to those who suffered from the 2011 earthquake and tsunami, which killed about 19,000 people.

All three cities still in the running are hoping that the Olympics will not only increase national pride, but also fatten the national wallet.

Opinions about the economic impact of hosting the Olympics vary.

Leading up to the games, the Olympics represent a serious expenditure. The Chinese government spent $40 billion on infrastructure in Beijing between 2002 and 2006, while preparations for the 2004 Athens Summer Olympics cost around $11 billion. This money does go to construction companies and back into the economy -- unemployment in Barcelona fell from 18.4 percent to 9.6 percent between 1986 and 1992 -- but it's an expense nonetheless.

However, Athenians are still benefiting from the updates to airports, subways, roads and pedestrian walkways made for the '04 Games, as have the residents of Sydney and Atlanta.

The games also bring in serious tourism and investment dollars in both the short- and long-term. The Bank of England predicted last week that the London Summer Games, just two months away, could end the nation's double-dip recession. Sydney made close to $10 billion in tourism spending over two years thanks to the 2000 Olympics, plus another $1 billion in sponsorship revenues. London is hoping that these games will give the country a similar, much needed, boost in the third quarter of 2012.

But an Olympics' success depends largely on how it is measured.

In terms of an identifiable macroeconomic impact, I think it's hard to think of any good examples where it's shown up in the GDP figures, Stefan Szymanski, a professor of sports management at the University of Michigan, recently told The Guardian.

As economic events, they're not a big deal. Economics is about more mundane things like producing steel and cars and working in offices -- we have Olympics to take our minds off the dull things that make the money.

Indeed, there are long-term benefits, as well as long-term costs.

A 2009 study from British investment firm Locate in Kent found that the annual cost of maintaining Olympic venues can run as high as $780 million, about the same amount that Sydney made in ticket sales in 2000.

The Sydney 2000 Olympic Games provided massive exposure and publicity to the world and in many cases a first or a renewed awareness of Australia, Locate in Kent said in its report. The business opportunities identified and the networks established internationally ... will continue to provide opportunities into the future for Australian business and trade, particularly in the Asia-Pacific region, where Australia has a growing status as a stable and developed country.

The IOC will make its final vote on Sept. 7, 2013, in Buenos Aires, but regardless of which country eventually wins the IOC bid, the host city will benefit in some way. Whether it provides a psychological boost, like in Japan; a cultural one, like in the rising world power of Turkey; or an economic one, as is badly needed in Spain, which has Europe's highest unemployment rate, the Olympics will be worth the cost.