Charitable giving in the US has surged to a record high, shattering the $400 billion benchmark for the first time.

And most of the money went to religious causes, according to Giving USA 2018: The Annual Report on Philanthropy for the Year 2017, which was released Tuesday.

Giving amounted to an estimated $410.02 billion in 2017, increasing more than 5 percent (3 percent adjusted for inflation) over the revised total donated in 2016.

The contributions from individuals made up 70 percent of total giving.

"As we looked at the data this year, one of the things that was very clear is just the generosity of Americans – that they are committed to investing in causes they care about across our society," said Rick Dunham, Giving USA Foundation vice chair, and CEO, Dunham+Company, at a news conference.

"Just the size of the charitable sector in America – at $410 billion, if you were to put that into a larger context – if it was its own country – it would have an economy bigger than Greece, or Austria, or Norway or Portugal," Dunham continued.

"Charitable contributions make up 2.1 percent of our GDP (gross domestic product)," he said.

The Giving USA publication credited a strong economy and booming stock market, citing a nearly 20 percent growth in the S&P 500.

"Investment returns funded multiple very large gifts, most of which were given by individuals to their foundations, including two gifts of $1 billion or more," said Amir Pasic, Ph.D., the Eugene R. Tempel dean of the Lilly Family School of Philanthropy.

"This tells us that some of our most fortunate citizens are using their wealth to make some significant contributions to the common good," he continued.

Contributions went up in nearly all categories of recipient charities and across the board in the four sources of giving. Those sources include individuals, foundations, bequests and corporations.

Although giving to religion had the smallest increase percentage (2.9) in 2017, the estimated amount of contributions to religion was substantially higher than what was given to the other recipient types.

The religion category, which is comprised of churches, congregations and religious media organizations, received more than $127 billion in contributions.

"The largest amount that Americans give to is to religion," Pasic told CBN News.

"In some ways the faith-based giving may be somewhat undercounted because organizations such as Catholic Charities or World Vision, which are faith-based, but would be counted in different categories rather than in religion," Pasic explained.

Giving USA: The Annual Report on Philanthropy in America has presented charitable giving information for more than 60 years.