query: SELECT ?item ?system ?type ?country ?usage ?date ?ageType
  WHERE {
    { SELECT ?item (COUNT(?s) AS ?usage)
             WHERE { ?item wdt:P31/wdt:P279* wd:Q23649976 .
                    { SELECT DISTINCT ?p WHERE {?prop wikibase:statementProperty ?p;
                                                      wdt:P31/wdt:P279* wd:Q24716199 } }
                    OPTIONAL { ?s ?p ?item }
                   } GROUP BY ?item }
    OPTIONAL { ?item wdt:P31/wdt:P361 ?system .
    OPTIONAL { ?system wdt:P17 ?country . }
    OPTIONAL { ?system wdt:P31/p:P279/pq:P642 ?type } }
    OPTIONAL { ?item p:P2899/pq:P8241 ?ageType }
    OPTIONAL { ?item wdt:P571 ?start } OPTIONAL { ?item wdt:P576 ?end }
    BIND ( IF ( bound(?end) ,
               concat(str(year(?start)),"–",str(year(?end))) ,
               concat(str(year(?start)),"–") ) AS ?date)
    } ORDER BY ?system ?item ?type