Are Syrian refugees in the U.S. likely to be affiliated with ISIS? So far, the math suggests native-born Americans are a far bigger source of concern.

The most comprehensive survey of Americans who’ve been charged with attempting to help ISIS finds that none of the 68 are Syrian or Syrian-American and that only three were refugees of any kind.

"ISIS Cases in the United States," compiled by Fordham University Law School's Center on National Security, notes instead that to date four out of five U.S. residents charged with supporting ISIS are American citizens and almost two-thirds are U.S.-born.

Moreover, the three ISIS sympathizers who were killed in attempts to carry out attacks in the U.S. -- in Texas and Boston -- were all U.S.-born citizens. Two were African-Americans and the other the son of a Catholic nurse and a Pakistani-American engineer.

“In the ISIS cases, there is NO trend suggesting the involvement of refugees … or Syrians,” said Karen Greenberg, director of the Center.

Key findings of the report, which the Center continually updates, show that the alleged ISIS supporters come from a variety of backgrounds, with only a few having ties to the Middle East. The report categorizes arrests made in a variety of jurisdictions over the past 18 months, since ISIS began its social media campaign in earnest.

Here are a number of the key datapoints:

--55 of the 68 arrested are U.S. citizens. Of the 55 citizens, 12 were naturalized, the rest American-born.

--Of the 25 not born in the U.S., seven were born in Europe -- all from the states of the former Yugoslavia; another six in Africa --Somalia, Ghana and and Sudan; six were born in the Middle East -- one each from Saudi Arabia, Iran, Iraq, Yemen, Egypt and Palestine; five were from Central Asia --Uzbekistan and Kazakhstan; and one was from Cuba.

--At least one-third of those arrested are converts to Islam.

--More than half of those charged, 36, allegedly wanted to travel to Syria to fight. Eighteen allegedly aspired to be domestic plotters, and Greenberg said the Justice Department's most recent investigations appear to be more focused on domestic plotters. The other 14 were a mixture of alleged aspiring recruiters and cyberterrorists.

--Eight have previous criminal records and many had been prescribed psychotropic drugs.

--Eight have family ties to others charged, which supports Greenberg's long-held belief that family radicalization is as least as important as radicalization through exposure to online jihadi propaganda.

--Most were men, but 10 of the 68 were women. The average age is 26.4 years, with the youngest in their teens and the oldest 44.

--The 68 come from 20 states, with New York and Minnesota accounting for 21 cases -- 12 in New York, nine in Minnesota.

So far, 18 of the 68 have pleaded guilty and seven have been sentenced with an average term of 10 years, three months.

Greenberg said that while stateless refugees are vulnerable to recruitment by terror groups, countries who provide a home to refugees make them less susceptible to recruitment. “If you’re looking for a counter-narrative to ISIS, which everyone is talking about, why not, ’ISIS is wrong. The U.S. WILL take care of Muslims, of Syrian refugees in need, and provide a constructive future.’ That is a strong counter-narrative.”