Question: When did the roof gardens above the neighborhood where Margaret Morris was born open to the public?

full_context: Document 1: Marjorie Cotton: Marjorie Cotton Isherwood, best known by the name Marjorie Cotton (1913–2003), was the first professionally qualified children's librarian in New South Wales, Australia. She initiated programs that are the basis of services to children in Australian public libraries today.
Document 2: Department store: All major cities have their distinctive local department stores, which anchored the downtown shopping district until the arrival of the malls in the 1960s. Washington, for example, after 1887 had Woodward & Lothrop and Garfinckel's starting in 1905. Garfield's went bankrupt in 1990, as did Woodward & Lothrop in 1994. Baltimore had four major department stores: Hutzler's was the prestige leader, followed by Hecht's, Hochschild's and Stewart's. They all operated branches in the suburbs, but all closed in the late twentieth century. By 2015, most locally owned department stores around the country had been consolidated into larger chains, or had closed down entirely.
Document 3: May O'Donnell: Born in Sacramento, California, May O'Donnell studied dance in San Francisco with Estelle Reed and performed in Reed's company before moving to New York City to study with Martha Graham. O'Donnell was a member of the Martha Graham Dance Company from 1932 until 1938.
Document 4: Plymouth: In 2004 the old Drake Circus shopping centre and Charles Cross car park were demolished and replaced by the latest Drake Circus Shopping Centre, which opened in October 2006. It received negative feedback before opening when David Mackay said it was already "ten years out of date". In contrast, the Theatre Royal's production and education centre, TR2, which was built on wasteland at Cattedown, was a runner-up for the RIBA Stirling Prize for Architecture in 2003.
Document 5: Department store: The design and function of department stores in Germany followed the lead of London, Paris and New York. Germany used to have a number of department stores; nowadays only a few of them remain. Next to some smaller, independent department stores these are Karstadt (in 2010 taken over by Nicolas Berggruen, also operating the KaDeWe in Berlin, the Alsterhaus in Hamburg and the Oberpollinger in Munich), GALERIA Kaufhof (part of the Metro AG). Others like Hertie, Wertheim and Horten AG were taken over by others and either fully integrated or later closed.
Document 6: Marie Sallé: Marie Sallé (1707–1756) was a French dancer and choreographer in the 18th century known for her expressive, dramatic performances rather than a series of "leaps and frolics" typical of ballet of her time.
Document 7: Kensington Roof Gardens: The building housed the department store Derry and Toms until 1973, and then Biba until 1975. Since the 1980s the garden has been used as a restaurant and club.
Document 8: Department store: All the major British cities had flourishing department stores by the mid-or late nineteenth century. Increasingly, women became the major shoppers and middle-class households. Kendals (formerly Kendal Milne & Faulkner) in Manchester lays claim to being one of the first department stores and is still known to many of its customers as Kendal's, despite its 2005 name change to House of Fraser. The Manchester institution dates back to 1836 but had been trading as Watts Bazaar since 1796. At its zenith the store had buildings on both sides of Deansgate linked by a subterranean passage "Kendals Arcade" and an art nouveau tiled food hall. The store was especially known for its emphasis on quality and style over low prices giving it the nickname "the Harrods of the North", although this was due in part to Harrods acquiring the store in 1919. Other large Manchester stores included Paulden's (currently Debenhams) and Lewis's (now a Primark).
Document 9: Margaret Morris (dancer): Margaret Morris (1891 in Kensington, London, England – 29 February 1980 in Glasgow, Scotland) was a British dancer, choreographer and teacher. She was the first proponent of the Isadora Duncan technique in Great Britain. She founded the Margaret Morris Movement, Celtic Ballet, and two Scottish National Ballets in Glasgow (1947) and in Pitlochry (1960). Morris devised a system of movement notation, which was first published in 1928.
Document 10: Department store: The middle up segment is mainly occupied by Metro Department Store originated from Singapore and Sogo from Japan. 2007 saw the re-opening of Jakarta's Seibu, poised to be the largest and second most upscale department store in Indonesia after Harvey Nichols, which the latter closed in 2010 and yet plans to return. Other international department stores include Debenhams and Marks & Spencer. Galeries Lafayette also joins the Indonesian market in 2013 inside Pacific Place Mall. This department store is targeting middle up market with price range from affordable to luxury, poised to be the largest upscale department store. Galeries Lafayette, Debenhams, Harvey Nichols, Marks & Spencer, Seibu and Sogo are all operated by PT. Mitra Adiperkasa.
Document 11: Neues Schauspielhaus: While the auditorium was destroyed in World War II, the facade as well as the cinema survived and in 1951 was renamed the Metropol. Since 1977 it has been used as a discothèque and became a famous music club during the 1980s heyday of West Berlin, frequented by bands like Depeche Mode, Morrissey, The Cross, The Human League and Front 242. For a short time in 2000 it was the location of the KitKatClub and in 2005 the architect Hans Kollhoff remodeled the interior as the "Goya" night club.
Document 12: Meryl Tankard: Meryl Tankard AO (born 1955, Darwin, Northern Territory) is an Australian dancer and choreographer who has a wide national and international reputation.
Document 13: Margaret Leng Tan: She was born in Singapore on 12 December 1945, the daughter of former Straits Times Press chairman Tan Chye Cheng, and started taking music lessons at the age of six. In 1961 the young Tan took first place in the Singapore-Malaysia annual piano competition, and won a scholarship to study at The Juilliard School at age 16 in the following year. In 1971 she became the first woman to earn a Doctorate in Musical Arts at Juilliard, and became the diva of the prepared piano, inserting nuts and bolts into the instrument and playing it inside out to rave reviews.
Document 14: Anna Pavlova: Anna Pavlovna (Matveyevna) Pavlova (Russian: Анна Павловна (Матвеевна) Павлова; February 12 (O.S. January 31) 1881 -- January 23, 1931) was a Russian prima ballerina of the late 19th and the early 20th centuries. She was a principal artist of the Imperial Russian Ballet and the Ballets Russes of Sergei Diaghilev. Pavlova is most recognized for the creation of the role The Dying Swan and, with her own company, became the first ballerina to tour ballet around the world.
Document 15: Marge Champion: Marjorie Celeste "Marge" Champion (née Belcher; born September 2, 1919) is an American dancer, choreographer, and stage and screen actress. At a young age, she was hired as a dance model for Walt Disney Studios animated films. Later, she performed as an actress and dancer in film musicals, and in 1957 had a TV show based on song and dance. She has also done creative choreography for liturgy, and served as a dialogue and movement coach for the 1978 TV miniseries, "The Awakening Land", set in the late 18th century in the Ohio Valley.
ground_truth: 1980s
sub_queries: Margaret Morris >> place of birth Answer: Kensington
when did the roof gardens above Kensington open to the public Answer: 1980s