Consumers buying virtual currency inside free mobile games are spending an average of $14 per transaction, according to mobile analytics firm Flurry.

While nearly three-fourths or 71 percent of people buy virtual currency in increments of between 0 and $10, most of those purchases are around the $9.99 level, followed by $4.99 and $0.99. Consumers actually spend $0.99 less than 2 percent of the time.

“The higher order decision consumers of freemium games make is simply whether or not to spend,” wrote Jeferson Valadares, Flurry’s general manager for games. “Our data shows that around 3% of consumers will spend money in freemium games.”

At the other end, 5 percent of all purchases are for $50 or more. Those $50-plus purchases actually generate 30 percent of the revenue of games Flurry studied. These are the infamous “whales,” the relatively rare but lucrative category of consumers who spend outsize amounts of money on virtual currency.

“If you’re a game designer, your main take away is that very few transactions, and consumers who complete those transactions, make up the bulk of your revenue,” Valadares wrote. “Therefore, your own “meta-game” should be about whale hunting.”

Flurry, which has analytics in more than 75,000 mobile apps on iOS and Android estimates that game revenue from both platforms will surpass $1 billion this year.