How many {choreographer} are to/by {Frederick Ashton} ?
How many choreographed dances can be attributed to Frederick Ashton?
How many choreographs did  FrederickAshton do
SELECT ( COUNT ( ?l ) AS ?t ) { ?l property:choreographer resource:Frederick_Ashton }
SELECT (COUNT(?sub) AS ?subs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?sub .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1809> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q711073 .
} 

SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P1809 wd:Q711073 }
11