Haw. Rev. Stat. § 53-30

With the approval of the redevelopment agency, the articles of association, or amended articles, may authorize the issuance of income debenture certificates bearing no greater interest than six per cent a year. The income debenture certificates and any instrument under which they are issued may contain other provisions, including provisions for amortization by serial maturities, through the operation of a sinking fund or otherwise, which may be approved by the agency.