Section 33. A credit union may also contract, on terms to be agreed upon, with a person eligible for membership in the credit union or a member of such person's family, for the deposit at intervals within a period of 12 months, of sums of money, to be known as club deposits, and may pay interest or dividends thereon in the amount decided by its board of directors, but at no higher rate than that paid on its regular deposits or as regular dividends on shares.