CREATE TABLE table_201_25 (id DECIMAL, "party" TEXT, "leader" TEXT, "from" TEXT, "to" TEXT)

what is the total number of years gordon wallace and robert cunning spent in office .
SELECT SUM("to" - "from") FROM table_201_25 WHERE "leader" IN ('gordon wallace', 'robert cunning')
SELECT SUM("to" - "from") FROM "table_201_25" WHERE "leader" IN ('gordon wallace', 'robert cunning')