Question: when did the right to buy scheme start
[{'answer': '1980', 'provenance': [{'wikipedia_id': '2063383', 'title': 'Right to Buy', 'start_paragraph_id': 1, 'start_character': 535, 'end_paragraph_id': 1, 'end_character': 539, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2063383', 'title': 'Right to Buy', 'start_paragraph_id': 8, 'start_character': 0, 'end_paragraph_id': 8, 'end_character': 673, 'bleu_score': 0.9825310706027971, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9656303345780736181}, 'section': 'Section::::History.:Thatcher policies.\n'}]}, {'provenance': [{'wikipedia_id': '2063383', 'title': 'Right to Buy', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 539, 'bleu_score': 0.8970987334624251, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9656303345780736181}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2063383', 'title': 'Right to Buy', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['About 1,500,000 homes in the UK have been sold in this manner since the introduction of the scheme in 1980, with the scheme being cited as one of the major factors in the drastic reduction in the amount of social housing in the UK, falling from nearly 6.5 million units in 1979 to roughly 2 million units in 2017, while also being credited as the main driver of the 15% rise in home ownership, which rose from 55% of householders in 1979 to a peak of 71% in 2003 (though this figure has declined since the late 2000s to 63% in England specifically in 2017', 'The Right to Buy scheme is a policy in the United Kingdom (with the exception of Scotland since 1 August 2016 and Wales from 26 Jan 2019) which gives secure tenants of councils and some housing associations the legal right to buy, at a large discount, the council house they are living in. There is also a Right to Acquire for assured tenants of housing association homes built with public subsidy after 1997, at a smaller discount. About 1,500,000 homes in the UK have been sold in this manner since the introduction of the scheme in 1980', 'The Right to Buy scheme is a policy in the United Kingdom (with the exception of Scotland since 1 August 2016 and Wales from 26 Jan 2019) which gives secure tenants of councils and some housing associations the legal right to buy, at a large discount, the council house they are living in. There is also a Right to Acquire for assured tenants of housing association homes built with public subsidy after 1997, at a smaller discount. About 1,500,000 homes in the UK have been sold in this manner since the introduction of the scheme in 1980, with the scheme being cited as one of the major factors in the drastic reduction in the amount of social housing in the UK, falling from nearly 6.5 million units in 1979 to roughly 2 million units in 2017, while also being credited as the main driver of the 15% rise in home ownership, which rose from 55% of householders in 1979 to a peak of 71% in 2003 (though this figure has declined since the late 2000s to 63% in England specifically in 2017).']}}]}]