CREATE TABLE table_23180 ("Institution" TEXT, "Location" TEXT, "Nickname" TEXT, "Founded" FLOAT, "Type" TEXT, "Enrollment" FLOAT, "Joined" FLOAT)

When did the school from Logan Township, Pennsylvania join the Conference?
SELECT "Joined" FROM table_23180 WHERE "Location" = 'Logan Township, Pennsylvania'
SELECT "Joined" FROM "table_23180" WHERE "Location" = 'Logan Township, Pennsylvania'