Answer based on context:

The Dutch Reformed Church went with migrants to the Americas, beginning in 1628 in New Amsterdam. St. Thomas Reformed Church, founded in 1660 in St. Thomas, Danish West Indies, became the first Dutch Reformed Church in the Caribbean. During the period of Dutch settlement in Brazil in the 17th century colonists organised the Reformed Churchin Pernambuco. In Canada and the United States, the oldest and second largest body is the Reformed Church in America, which was the American branch of the Dutch Reformed Church in the Netherlands between 1628 and 1819.  The largest Dutch Reformed body in North America, the Christian Reformed Church in North America, split off from Reformed Church in America in 1857. Smaller related denominations and federations include the Canadian and American Reformed Churches, the Free Reformed Churches of North America , the Heritage Reformed Congregations , the Netherlands Reformed Congregations , the Protestant Reformed Churches in America , and the United Reformed Churches in North America . Former US Presidents Martin Van Buren and Theodore Roosevelt, both of Dutch descent, were affiliated with the Dutch Reformed Church.

How many former US Presidents were affiliated with the Dutch Reformed Church?
2