Question: When Saint Petersburg has its population 2.92e+06?
Paraphrase: When was the population of Saint Petersburg 2.92e+06?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q656 p:P1082 ?s . ?s ps:P1082 ?x filter(contains(?x , '2.92e+06')) . ?s pq:P585 ?value}