Question: when did ken griffey jr won the homerun derby
[{'answer': '1998', 'provenance': [{'wikipedia_id': '813519', 'title': 'Home Run Derby', 'start_paragraph_id': 29, 'start_character': 118, 'end_paragraph_id': 29, 'end_character': 122, 'bleu_score': 1.0, 'section': 'Section::::Television and radio coverage.\n'}]}, {'provenance': [{'wikipedia_id': '813519', 'title': 'Home Run Derby', 'start_paragraph_id': 31, 'start_character': 0, 'end_paragraph_id': 31, 'end_character': 401, 'bleu_score': 0.9712154609069981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5812548951876737027}, 'section': 'Section::::Television and radio coverage.\n'}]}]