Question: how long have we been celebrating pi day
[{'answer': '2009', 'provenance': [{'wikipedia_id': '25013', 'title': 'Pi Day', 'start_paragraph_id': 1, 'start_character': 196, 'end_paragraph_id': 1, 'end_character': 200, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': '1988', 'provenance': [{'wikipedia_id': '25013', 'title': 'Pi Day', 'start_paragraph_id': 5, 'start_character': 3, 'end_paragraph_id': 5, 'end_character': 7, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '25013', 'title': 'Pi Day', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 280, 'bleu_score': 0.7995389546140481, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 700534659587871090}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '25013', 'title': 'Pi Day', 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 320, 'bleu_score': 0.96188712955549, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 700534659587871090}, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '25013', 'title': 'Pi Day', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 373, 'bleu_score': 0.8149253562453661, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 700534659587871090}, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '25013', 'title': 'Pi Day', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 0, 'bleu_score': 1.0, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 700534659587871090}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '25013', 'title': 'Pi Day', 'section': 'Section::::History.\n', 'start_paragraph_id': 5, 'end_paragraph_id': 5, 'meta': {'evidence_span': ['In 1988, the earliest known official or large-scale celebration of Pi Day was organized by Larry Shaw at the San Francisco Exploratorium, where Shaw worked as a physicist, with staff and public marching around one of its circular spaces, then consuming fruit pies.', 'In 1988, the earliest known official or large-scale celebration of Pi Day was organized by Larry Shaw at the San Francisco Exploratorium, where Shaw worked as a physicist, with staff and public marching around one of its circular spaces, then consuming fruit pies. The Exploratorium continues to hold Pi Day celebrations.', 'In 1988, the earliest known official or large-scale celebration of Pi Day was organized by Larry Shaw at the San Francisco Exploratorium, where Shaw worked as a physicist, with staff and public marching around one of its circular spaces, then consuming fruit pies. The Exploratorium continues to hold Pi Day celebrations.']}}]}]