The American Jewish population is declining in its religious observance, according to the 2008 American Religious Identification Survey.
The survey found that of the 5.4 million American Jews, only 3.4 million call themselves religious. That is a 20 percent decline since 1989.
The study also noted that 37 percent consider themselves only culturally Jewish and Jews are more likely to be secular than Americans.
Researchers said this is because there is a growing rate of inter-faith marriages.
More than 900 self-identified Jews were surveyed. The study has been conducted once every decade since 1990.