When the United States hosted the World Cup in 1994, it set records with 3.6 million spectators and an average of almost 69,000. The first 20 Copa America matches through Sunday averaged 40,429.
"It's not a World Cup, so we were not expecting to sell out every game," U.S. Soccer Federation President Sunil Gulati said. "Our baseline projection going into the tournament had been 30,000 per game."
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Mexico has drawn two of the four biggest crowds, 83,263 to Pasadena's Rose Bowl for its 2-0 victory over Jamaica and 60,025 to Glendale, Arizona, for its 3-1 win over Uruguay. Also in the top four were a pair of matches in Santa Clara, California, the United States' 2-0 loss to Colombia in the tournament opener (64,719) and for Argentina's 2-1 win over Chile (60,025).
Two of the four smallest crowds were in Orlando, Florida, for Costa Rica-Paraguay (17,113) and Panama-Bolivia (13,466). Other low draws were Ecuador-Peru in Glendale (a tournament-low 11,937) and Chile-Bolivia in Foxborough, Massachusetts (19,690).
"You can't compare this Copa America to what happened in 1994. 1994 was just the first time we've gotten the biggest event in the world," said Marcelo Balboa, a defender on the '94 U.S. team and now a Univision analyst. "In group stage in a World Cup, sometimes they don't all sell out, but once you get into that knockout quarterfinals, semifinals, I think you'll see the stadiums being packed."
Last year's Copa America in Chile averaged 25,223, according to figures in match reports. The 2011 tournament in Argentina averaged just under 34,000 and the 2007 edition in Venezuela about 40,000.
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Capacity of the U.S. stadiums is larger, far fewer fans traveled to the U.S. for the Copa America than the World Cup and a lower percentage of seats is set aside for sponsors.
Ticket prices impact attendance. The tournament's cheapest seat is $50. Lower-level seats were listed at $60-$230 for last Saturday's game between the United States and Paraguay in Philadelphia, and listed prices run from $177.50-$2,013 for the June 26 final in East Rutherford, New Jersey.
"When I first saw the ticket prices, I said 'No way.' I'm not going to pay $200 for a ticket in the end zone. I'll just stay home and watch it on TV," said Renato De Araujo, a 37-year-old who grew up in Brazil and watched the Selecao's 7-1 rout of Haiti in Orlando. "But as the game gets closer, I got more excited and started looking online for tickets and found some for $150 and decided to go. It's Brazil. How many times are you going to see them in your town?"
When the U.S. hosted the World Cup, venues were announced 27 months ahead of the tournament and ticket sales began in February 1993, with seats priced at $25-$475.
Because of corruption investigations alleging hundreds of millions of dollars in bribes to regional soccer leaders, the USSF demanded Copa America commercial and broadcast agreements be renegotiated and did not confirm it would host the tournament until last October. Sites were announced the following month, and ticket sales started in late January.
"Given the difficulties of the last year, which are well known, we went on sale and finalized our hosting the event later than would have been normal," Gulati said.
The start of the tournament coincided with the NBA and Stanley Cups finals, and Paraguay coach Ramon Diaz said it was understandable attention of many U.S. sports fans was directed at basketball and hockey rather than soccer.
And while the ability to watch top-level soccer was a rarity in the U.S. two decades ago, now every Premier League and Champions League match is available on live television.
"With the touch of a phone or the press of a computer, you can find out what anyone's doing in any country," said former American. goalkeeper Brad Friedel, now a commentator for Fox.
And because of the EPL and Champions League, many clubs have a larger following than national teams in the U.S.
"Manchester United, Arsenal, Chelsea, Liverpool, they put a lot of money into the United States," Balboa said. "I don't think South American teams put that much money here yet."
For more on the COPA America competition including stats and scores, click here.