CREATE TABLE table_204_191 (id DECIMAL, "title" TEXT, "artist" TEXT, "year" TEXT, "location/gps coordinates" TEXT, "material" TEXT, "dimensions" TEXT, "owner" TEXT)

how many are owned by the national park service ?
SELECT COUNT(*) FROM table_204_191 WHERE "owner" = 'national park service'
SELECT COUNT(*) FROM "table_204_191" WHERE "owner" = 'national park service'