Question: Which calender day of a given year has maximum time index?
Paraphrase: What day out of the year is the longest time index?
SPARQL (Wikidata): select ?ent where { ?ent wdt:P31 wd:Q47150325 . ?ent wdt:P4895 ?obj } ORDER BY DESC(?obj)LIMIT 5 
Answer: 2 March 2018, 1 January 1900