Japan’s top grossing free-to-play mobile game Puzzle & Dragons for iOS and Android is estimated to generate between five billion yen ($54 million) to seven billion yen ($75.5 million) a month in the country, according to the Japanese press as translated by industry watcher and analyst Dr. Serkan Toto.

The estimated revenue range is based off a financial document for January 2013 that accompanied game company GungHo Online’s financial report for the 2012 fiscal year. According to the report for the fiscal year of 2012, the company saw sales grow 168.8 percent year-over-year to $280 million and operating profit increase 690.1 percent to $99 million.

In January 2013 alone, the company revealed that it saw sales of 8.5 billion yen ($92 million), a 1002.4 percent increase year-over-year. GungHo didn’t provide a platform or a specific game in its portfolio for the figures it saw last month, but that didn’t stop the Japanese press from publishing estimates about the amount of revenue Puzzle & Dragons contributed toward the $92 million GungHo saw in January 2013.

“There is absolutely no doubt in the industry over here that one game only — Puzzle & Dragons — is the main driver behind this growth,” Toto says on his blog.

The three Japanese outlets to publish estimates included Inside Games’ estimate of seven billion yen ($75.5 million), Projetista’s estimate of six billion yen ($64.6 million) and Popular Social App and Game Analysis Blog’s estimate of five billion yen ($54 million. The three estimates average out to $64.7 million, translating to about an average of $2 million in revenue per day from Puzzle & Dragons. In comparison, Finish developer Supercell was reported to be generating $1 million in gross revenue a day from two games — Hay Day and Clash of Clans. Also, Electronic Arts’ The Simpsons: Tapped Out pulled in $23 million in three months.

The puzzle and RPG hybridPuzzle & Dragons, which added moved from seven million to eight million registered users in 12 days, is a puzzle and RPG hybrid game which first launched in Japan for iPhone in February 2012 and in the U.S. in November 2012. In spite of this popularity in Japan, the game still has yet to find a sizable audience here in the States, though it’s already starting to see similar titles appear in North America like Renren’s new puzzle game Merlin’s Rage.

GungHo, known for hosting the servers for massively multiplayer online role-playing game Ragnarok Online, currently has a market cap of $2.9 billion, more than Zynga’s $2.5 billion and GREE’s $2.8 billion, but well below DeNA’s $3.6 billion market cap.