CREATE TABLE table_66586 ("School" CLOB, "Location" CLOB, "Mascot" CLOB, "Enrollment" FLOAT, "IHSAA Class" CLOB, "# / County" CLOB, "Year Joined" FLOAT)

what is the enrollement for the year joined 1958 in clarksville?
SELECT SUM("Enrollment") FROM table_66586 WHERE "Year Joined" = '1958' AND "Location" = 'clarksville'
SELECT SUM("Enrollment") FROM "table_66586" WHERE "Location" = 'clarksville' AND "Year Joined" = '1958'