How many ducks did Don Bradman score in Test cricket?

During Sir Donald Bradman's incredible cricketing career, he made a total of 211 centuries, played 80 tests for Australia (most of them as captain), and made 6996 test runs. In the English summer of 1930 Bradman scored 974 runs over the course of the five Ashes tests, the highest individual total in any test series. Bradman's batting average of 99.94 from his 52 Tests was nearly double the average of any other player before or since.