a One 30 years, one 33 years, and one 38 years. b One 30 years, one 33 years, one 35 years, one 37 years, one 33 years, and one 42 years. TABLE B.—FREQUENCY OF ISSUE OF SERIES, [This table includes serial associations only, those operating under the permanent and terminating plans having been omitted for reasons that will be seen by reference to the explanation of the plans on pages 22 to 24.] |