The survey, conducted by a consortium of Jewish federations and communities, shows that Jews are increasing their educational attainments and on average hold higher socioeconomic positions than other U.S. citizens.
About 177,000 randomly selected Americans, both Jews and non-Jews, were interviewed by United Jewish Communities as part of the $6 million, once-a-decade study.
The findings state that the number of Jews in the country has declined by 5 percent, from 5.5 million in 1990 to 5.2 million in 2002, partly due to a decreasing birthrate.
The median age of Jews increased from 37 to 41, and the percentage of Jews under 21 fell from 21 percent to 19 percent.
But the study also found that increasing numbers of Jews are graduating from higher education institutions -- 55 percent of Jews over 18 have a bachelor's degree compared to 28 percent of non-Jews.
"(The study shows that) we are a very successful community, highly educated, very actively engaged in (our) professions and lives but unfortunately declining by virtue of an aging population," said Gail Hyman, senior vice president of marketing and public affairs for UJC.
The report also states that the Jewish population is not only declining because of aging but because of a declining Jewish birthrate.
More Jewish women nationwide are forgoing or delaying having children in favor of higher education, the study found.
Hyman said the declining birthrates also are characteristic of a higher socioeconomic strata.