The Saturn was initially successful in Japan but failed to sell in large numbers in the United States after its surprise May 1995 launch, four months before its scheduled release date. After the debut of the Nintendo 64 in late 1996, the Saturn rapidly lost market share in the U.S., where it was discontinued in 1998. Having sold 9.26 million units worldwide, the Saturn is considered a commercial failure; the failure to release a game in the "Sonic the Hedgehog" series, known in development as "Sonic X-treme", is considered a factor in the poor performance. The Saturn was succeeded in 1998 by the Dreamcast.