CREATE TABLE table_78736 ("President" TEXT, "Date of inauguration" TEXT, "Age at inauguration" TEXT, "End of term" TEXT, "Length of retirement" TEXT, "Lifespan" TEXT)

What is the Length of retirement of the President with an Age at inauguration of 70years, 53days?
SELECT "Length of retirement" FROM table_78736 WHERE "Age at inauguration" = '70years, 53days'
SELECT "Length of retirement" FROM "table_78736" WHERE "Age at inauguration" = '70years, 53days'