CREATE TABLE table_22347 ("State  ( class ) " CLOB, "Vacator" CLOB, "Reason for change" CLOB, "Successor" CLOB, "Date of successors formal installation" CLOB)

How many reasons were given when A. Willis Robertson (D) resigned?
SELECT COUNT("Reason for change") FROM table_22347 WHERE "Vacator" = 'A. Willis Robertson (D)'
SELECT COUNT("Reason for change") FROM "table_22347" WHERE "Vacator" = 'A. Willis Robertson (D)'