What is {population} of {Madagascar} that is {point in time} is {1999-0-0} ?
What was Madagascar's population in 1999?
What is the population of Madagascar in the year 1999?
SELECT ?r WHERE { FILTER ( CONTAINS ( YEAR ( ?z ) , '1999' ) ) . ?v property:population ?r . ?v property:point_in_time ?z . resource:Madagascar property:population ?v }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q1019> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1082> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P585> <1999-0-0>
} 

SELECT ?obj WHERE { wd:Q1019 p:P1082 ?s . ?s ps:P1082 ?obj . ?s pq:P585 ?x filter(contains(YEAR(?x),'1999')) }