PREFIX schema: <https://schema.org/>

SELECT ?country (SUM(?sale) AS ?revenue)
WHERE {
    GRAPH ?orderGraph {
        ?order schema:orderedItem ?orderItem ;
               schema:orderDelivery ?delivery .
        ?orderItem schema:orderQuantity ?quantity ;
                   schema:price ?price .
        ?delivery schema:deliveryAddress ?address .
        ?address schema:addressCountry ?country .
        BIND(?quantity * ?price AS ?sale)
    }
}
GROUP BY ?country
ORDER BY DESC(?revenue)
LIMIT 10

PREFIX schema: <https://schema.org/>

SELECT ?month (SUM(?sale) AS ?revenue)
WHERE {
    GRAPH ?orderGraph {
        ?order a schema:Order ;
               schema:orderDate ?orderDate ;
               schema:orderedItem ?orderItem .
        ?orderItem schema:orderQuantity ?quantity ;
                   schema:price ?price .
        BIND(?quantity * ?price AS ?sale)
        BIND(SUBSTR(STR(?orderDate), 1, 7) AS ?month)
    }
}
GROUP BY ?month
ORDER BY ?month