Question: In what year did the last fluent speaker of the language spoken by the Okehocking Tribe die?

Context articles: Takelma language
Verdena Parker
Wappo language
Tututni language
Makah language
Doris McLemore
Marie Wilcox
Ngarnji language
Okehocking people
Unami language

Takelma was the language spoken by the Latgawa and Takelma people and Cow Creek band of Upper Umpqua.
 It was first extensively described by Edward Sapir in his graduate thesis, "The Takelma Language of Southwestern Oregon".
 The last fluent speaker of Takelma, with whom Sapir worked while writing about the language, was Frances Johnson (Gwísgwashãn).
Verdena Parker is the last fluent speaker of the Hupa language, an Athabaskan language spoken by the Hoopa Valley Tribe, indigenous to northern California.
 While other children of her generation were sent to boarding schools, isolating them from their families, Parker was raised by her grandmother, who spoke Hupa with her.
 Through adulthood, Parker continued to speak Hupa with her mother daily, maintaining a high level of fluency despite language loss in the rest of the Hupa community.
Wappo is an extinct language that was spoken in the Alexander Valley north of San Francisco by the Wappo Native Americans.
 The last fluent speaker, Laura Fish Somersal, died in 1990.
 Wappo's language death is attributed to the use of English in schools and economic situations such as the workplace.
 According to Somersal, the name for the people and language is derived from the Spanish word "guapo", meaning "handsome" or "brave".
 The name for the people was originally Ashochimi.
Tututni ("Dotodəni", alternatively "Tutudin"), also known as Coquille and (Lower) Rogue River, is an extinct Athabaskan language once spoken by three Tututni (Lower Rogue River Athabaskan) tribes: Tututni tribe (including Euchre Creek band), Coquille tribe, and Chasta Costa tribe who are part of the Rogue River Indian peoples of southwestern Oregon.
 Ten speakers remained in 1961; the last fluent speaker died in 1983.
 In 2006 students at Linfield College participated in a project to "revitalize the language."
 It is one of the four languages belonging to the "Oregon Athabaskan" cluster of the Pacific Coast Athabaskan languages.
The Makah language is the indigenous language spoken by the Makah people.
 Makah has not been spoken as a first language since 2002, when its last fluent native speaker died.
 However, it survives as a second language, and the Makah tribe is attempting to revive the language, including through preschool classes.
 The endonymous name for Makah is qʷi·qʷi·diččaq.
Doris Jean Lamar-McLemore (April 16, 1927 – August 30, 2016) was an American teacher who was the last fluent speaker of the Wichita language, a Caddoan language spoken by the Wichita and Affiliated Tribes, indigenous to the U.S. states of Oklahoma and Texas.
Marie Wilcox is the last fluent speaker of Wukchumni, a dialect of Tule-Kaweah, which is a Yokutsan indigenous language spoken by the Tule-Kaweah Yokuts of California.
 She and her daughter teach interested members of their tribe; however, "few seem devoted to learn."
 She spent more than seven years working on a Wukchumni dictionary, which was published in 2014.
 As of 2014, it was estimated that the Wukchumni tribe had fewer than 200 members, of which Marie was the only fluent speaker of the language.
The Ngarnji (Ngarndji) language, Ngarnka (Ngarnga, Ngarnku), is the language traditionally spoken by the Ngarnji people of the Barkly Tablelands in the Northern Territory of Australia.
 The last fluent speaker of the language died between 1997 and 1998.
 Ngarnka belongs to the Mirndi language family, in the Ngurlun branch.
 It is closely related to its eastern neighbours Binbinka, Gudanji and Wambaya.
 It is more distantly related to its western neighbour Jingulu, and three languages of the Victoria River District, Jaminjung, Ngaliwurru and Nungali.
 There is very little documentation and description of Ngarnka, however there have been several graduate and undergraduate dissertations written on various aspects of Ngarnka morphology, and a sketch grammar and lexicon of Ngarnka is currently in preparation.
The Okehocking Tribe (also known as Ockanickon) was a small band of Unami language-speaking Delaware Indians, who occupied an area along the Ridley and Crum creeks in Chester County, Pennsylvania.
 Part of that area is now known as Ridley Creek State Park.
 Along with the Schuylkill and Brandywine Indians, the Okehocking were known as "Unami" or "people down the river" by other tribes, in accordance with the Indian way of designating a tribe by geographical location.
Unami is an Algonquian language spoken by Lenape people in the late 17th-century and the early 18th-century, in what then was (or later became) the southern two-thirds of New Jersey, southeastern Pennsylvania and the northern two-thirds of Delaware, but later in Ontario and Oklahoma.
 It is one of the two Delaware languages, the other being Munsee.
 The last fluent speaker in the United States, Edward Thompson, of the Delaware Tribe of Indians, died on 31 August 2002.
 His sister Nora Thompson Dean (1907–1984) provided valuable information about the language to linguists and other scholars.