The exemption on the LA return for pension income is $6,000 if you are over age 65. According to the instructions for the LA IT-540:
Up to $6,000 of your annual retirement income may be exempted from state taxation if your filing status is single, head of household, married filing separately, or qualifying widow(er), and you are 65 years of age or older. If your filing status is married filing jointly, both you and your spouse are age 65 years or older, and each of you received annual retirement income, up to $6,000 of the annual retirement income that each taxpayer receives may be exempt from state taxation.