what is the {end time} for {Nnamdi Azikiwe} has {position held} as {President of Nigeria} ?
What was the time period during which Nnamdi Azikiwe was the President of Nigeria?
When was Nnamdi Azikiwe the President of Nigeria?
SELECT ?w WHERE { ?j property:position_held resource:President_of_Nigeria . resource:Nnamdi_Azikiwe property:position_held ?j . ?j property:end_time ?w }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q181782> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P39> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q500282> .
?statement <http://www.wikidata.org/entity/P582> ?value. 
} 

SELECT ?value WHERE { wd:Q181782 p:P39 ?s . ?s ps:P39 wd:Q500282 . ?s pq:P582 ?value}