var dataSet = [ {"year":2014, "name":"hoge", "group":"A", "count":200}, {"year":2013, "name":"test", "group":"C", "count":110}, {"year":2013, "name":"shimizu", "group":"B", "count":310}, {"year":2014, "name":"suzuki", "group":"A", "count":260}, {"year":2015, "name":"tanaka", "group":"C", "count":180}, {"year":2014, "name":"sato", "group":"B", "count":220}, {"year":2015, "name":"hello", "group":"B"
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