Mo. Rev. Stat. § 143.123: Taxes on annuities, pensions and retirement allowances, subtraction per taxpayer, maximums per year or six-month period.

Any six thousand dollar subtraction provided by law for annuities, pensions, and retirement allowances in total per taxpayer, as hereafter provided by subsequent law, shall be implemented in a maximum amount of six thousand dollars per year, or three thousand dollars for a six-month period.