Ordinal Date Identifier https://en.wikipedia.org/w/index.php?title=Ordinal_date&oldid=1061989434 https://www.commoncoreontologies.org/InformationEntityOntology A Decimal Date Identifier that designates some Day by using a number to indicate the sequential ordering of the Day since the beginning of the Year. An Ordinal Date Identifier may or may not also contain a number indicating a specific Year. If both numbers are included, the ISO 8601 ordinal date format stipulates that the two numbers be formatted as YYYY-DDD or YYYYDDD where [YYYY] indicates a year and [DDD] is the day of that year, from 001 through 365 (or 366 in leap years). Ordinal Date Decimal Date Identifier