Here are five facts about prayer, including survey data on Americans’ prayer habits and historical instances of prayer intersecting with the government:

1. The National Day of Prayer was enacted in 1952 by the Congress and President Harry S. Truman. As with the addition of “under God” to the Pledge of Allegiance in 1954, the move came during the Cold War and was seen as a way of contrasting the more religious United States with the officially atheistic Soviet Union.

2. The Freedom From Religion Foundation unsuccessfully challenged the National Day of Prayer in court. The 7th Circuit Court of Appeals ruled in 2011 that the group, which aims to promote the separation of church and state, did not have legal standing to challenge the law.

3. For many Americans, every day is a day of prayer. More than half (55%) of Americans say they pray every day, according to a 2014 Pew Research Center survey, while 21% say they pray weekly or monthly and 23% say they seldom or never pray. Even among those who are religiously unaffiliated, 20% say they pray daily. Women (64%) are more likely than men (46%) to pray every day. And Americans ages 65 and older are far more likely than adults under 30 to say they pray daily (65% vs. 41%).

4. A Pew Research Center survey conducted in 2014 found that 45% of Americans – and a majority of Christians (55%) – say they rely a lot on prayer and personal religious reflection when making major life decisions. The same survey found that 63% of Christians in the U.S. say praying regularly is an essential part of their Christian identity.

5. In 2014 – in the case Town of Greece v. Galloway – the Supreme Court ruled that U.S. legislative and administrative bodies may begin their sessions with a prayer. On some occasions, however, the high court has rejected other types of state-sponsored prayer. For instance, in 1962’s Engel v. Vitale, the court famously struck down a policy requiring public school students to begin their day with a nonsectarian prayer.

Source: http://www.pewresearch.org/