There's a green-tinged cloud circling Orlando as executives at Disney World and Universal Studios stare each other down with dollar-sign eyes to see who will become America's most expensive theme park.

The quibble began in earnest just over a week ago when Universal Studios raised its basic single-day ticket price from $85 to $88. Not one to be outdone, Disney then hiked its base price from $85 to $89.

The row would have ended there, but Universal decided on Thursday to match Mickey Mouse dollar for dollar, raising its price for the second time in a week by just $1 to $89. If the prices keep going up, you may need a scorecard to keep track.

Last June, the base admissions price to a Disney World park was $82, but by the end of the month it was raised to $85.

Orlando Sentinel columnist Beth Kassab thinks that a $100 Disney World ticket is not far off. Based on the park's history of raising prices by roughly 6 percent a year, or a little under $4, she speculates that tickets could hit $100 as early as 2014. That, she says, may cause some problems.

The moment you get to three digits, it has an emotional impact, Eli Portnoy, CEO of CultureRanch, a group that studies consumer behavior, claims in the column. It's a barrier no one wants to cross, and Disney is going to have to be careful about crossing it.

One hundred dollars is a far cry from 1971's general admission of $3.50 (not adjusted for inflation) and a whole other Frontierland. It could give Orlando's theme parks a reputation for being out of touch and out of reach for everyday families.

But maybe $100 is not such a big deal. After all, the $89 ticket price strictly grants you access to the park. It does not include parking, food or souvenirs that can easily make the price crack three digits.

Raising single-day ticket prices is a strategic move on the part of the parks. By increasing the single-day fare and offering multiday passes with discounted per-day admission, Universal and Disney are able to keep people on their properties longer so they can spend even more money on cotton candy and princess makeovers.

Yet, when single-day admission rises, so too does the multiday fare. Disney, for example, just raised the base price of a four-day ticket to $256, a five-day ticket to $268 and a seven-day pass to $288.

It's unclear why both Disney and Universal crave the dubious title of most expensive park, but if this week's actions are any indication, they're both trying hard to outdo each other for the bragging rights.

A new report from Themed Entertainment Assn. may hold a clue. Despite a recovering economy and numerous price hikes, theme park attendance in the United States rose 3 percent in 2011. The report further highlights how Universal is able to keep up with Disney: The Wizarding World of Harry Potter, which opened at Universal's Islands of Adventure park, accounted for about half of that increase.

While Universal saw the biggest increases, Disney and SeaWorld, which charges $82 for a single day, also saw a moderate rise in attendance. This spike in interest allowed these parks to hike fares, and, as long as tourists remain interested, we can expect that entry fees will continue to rise.