PeriodOfTime

rdf:type	rdf:type http://data.e-stat.go.jp/lod/terms/time#Year
rdf:type	rdf:type http://purl.org/dc/terms/PeriodOfTime
endDate	endDate 2015 ^^http://www.w3.org/2001/XMLSchema#gYear
startDate	startDate 2015 ^^http://www.w3.org/2001/XMLSchema#gYear