Question: What year was the house, in which the 1912 and 1924 candidate for president of the United States stayed, declared a National Historic Landmark?

Context articles: Maggie L. Walker National Historic Site
San Juan Bautista State Historic Park
Herndon Home
James B. Weaver House
Oscar W. Underwood House
Hinchliffe Stadium
Schuyler Mansion
Guthrie Historic District (Guthrie, Oklahoma)
List of U.S. National Historic Landmarks by state
Oscar Underwood

The Maggie L. Walker National Historic Site is a United States National Historic Landmark and a National Historic Site located at 110½ E. Leigh Street on "Quality Row" in the Jackson Ward neighborhood of Richmond, Virginia.
 The site was designated a U.S. National Historic Landmark in 1975.
 The National Historic Site was established in 1978 to tell the story of the life and work of Maggie L. Walker (1867-1934), the first woman to serve as president of a bank in the United States.
 It was built by George W. Boyd, father of physician, Sarah Garland Boyd Jones.
 The historic site protects the restored and originally furnished home of Walker.
 Tours of the home are offered by National Park Service rangers.
San Juan Bautista Plaza Historic District, also known as San Juan Bautista State Historic Park is a historic district in San Juan Bautista, California, United States, that is a National Historic Landmark and a California state historic park.
 It includes the Mission San Juan Bautista, the Jose Castro House (another National Historic Landmark), and several other buildings.
 It became a State Park in 1933 and was declared a National Historic Landmark in 1970.
The Herndon Home is a historic house museum and National Historic Landmark at 587 University Place NW, in Atlanta, Georgia.
 An elegant Classical Revival mansion with Beaux Arts influences, it was the home of Alonzo Franklin Herndon (1858-1927), a rags-to-riches success story who was born into slavery, but went on to become Atlanta's first black millionaire as founder and head of the Atlanta Life Insurance Company.
 The house was designed by his wife Adrienne, and was almost entirely built with African-American labor.
 The house was declared a National Historic Landmark in 2000, and had previously been declared a "landmark building exterior" by the city of Atlanta in 1989.
The James B. Weaver House is a historic house at 102 Weaver Road (United States Route 63) in Bloomfield, Iowa.
 Built in 1865, it was the home of James Weaver (1833-1912) until 1890.
 Weaver, a populist and anti-monopolist, was the Greenback candidate for President in 1880 and the Populist candidate in 1892.
 The house was declared a National Historic Landmark in 1975.
 It is now operated as a bed and breakfast inn.
The Oscar W. Underwood House is a historic house located at 2000 G Street in the Foggy Bottom neighborhood Northwest, Washington, D.C..
 It is nationally significant both for its association with Alabama politician Oscar Underwood (1862-1929) who lived here 1914-25, and also as the first long-term home of the Washington College of Law, the nation's first law school founded and run by women.
 It was declared a National Historic Landmark in 1976.
 The building presently houses a legal aid clinic operated by George Washington University.
Hinchliffe Stadium ( ) is a 10,000-seat stadium located in Paterson, New Jersey, USA.
 The venue was completed in 1932 and sits on a dramatic escarpment above Paterson's National Historic Landmark Great Falls, and surrounded by the city's National Landmark Historic District, the first planned industrial settlement in the nation (chartered 1792).
 It is one of only a handful of stadiums surviving nationally that once played host to significant Negro league baseball during America's Jim Crow era.
 The stadium was designated a National Historic Landmark in March 2013 and a Paterson Historic Landmark in May 2013.
 In December 2014 legislation passed in the United States Congress to in include the stadium in the Great Falls National Landmark District.
Schuyler Mansion is a historic house at 32 Catherine Street in Albany, New York, United States.
 The brick mansion is now a museum and an official National Historic Landmark.
 It was constructed from 1761 to 1765 for Philip Schuyler, later a general in the Continental Army and early U.S. Senator, who resided there from 1763 until his death in 1804.
 It was declared a National Historic Landmark on December 24, 1967.
 It is also a contributing property to the South End–Groesbeckville Historic District, listed on the National Register of Historic Places in 1984.
The Guthrie Historic District (GHD) is a National Historic Landmark District encompassing the commercial core of Guthrie, Oklahoma, US.
 According to its National Historic Landmark Nomination it is roughly bounded by Oklahoma Avenue on the north, Broad Street on the east, Harrison Avenue on the south, and the railroad tracks on the west; it also includes 301 W. Harrison Avenue.
 The National Historic Landmarks Program on-line document describes the boundaries as "14th Street, College Avenue, Pine Street and Lincoln Avenue.
 One building, the Logan County Courthouse, is at 301 E. Harrison Avenue, outside the main boundaries of the GHD," This article relies on the former source, which is more detailed.
 According to the 1998 nomination, the proposed district covered 31 acres .
 The nomination included 112 resources, classed as 69 contributing buildings, 38 non-contributing buildings, 1 non-contributing structure and 3 noncontributing objects.
 It was declared a National Historic Landmark in 1999 for its historic significance as the first capital of the Oklahoma Territory and of Oklahoma.
The United States National Historic Landmark Program is designed to recognize and honor the nation's cultural and historical heritage.
 The program was formally inaugurated with a series of listings on October 9, 1960; as of February 16, 2017, there are 2,596 designated landmarks.
 A National Historic Landmark (NHL) is generally a building, district, object, site, or structure, that is officially recognized by the United States government for its national historical significance.
 A National Historic Landmark District (NHLD) is a historic district that is recognized as an NHL.
 Its geographic area may include contributing properties that are buildings, structures, sites or objects, and it may include non-contributing properties.
Oscar Wilder Underwood (May 6, 1862 – January 25, 1929) was an American lawyer and politician from Alabama, and also a candidate for President of the United States in 1912 and 1924.
 He was the first formally designated floor leader in the United States Senate, and the only individual to serve as the Democratic leader in both the Senate and the United States House of Representatives.