How many {legal form} are to/by {sole proprietorship} ?
What are the legal forms are for the sole proprietorship} ?
SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P1454 wd:Q2912172 }
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/P1454> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q2912172 .
} 

Sole proprietorship has how many legal forms?