Listing and assessing of bank stock; branch banks

When any bank, banking company, firm, association, or corporation engaged in the banking business, chartered under the laws of this state, any other state, or the United States, or chartered under the laws of another country doing business in this state, shall operate a branch bank or banks, banking office or banking offices, in different municipalities wholly within the limits of the parish of its legal domicile, its tax assessment for state and local purposes may be assessed at its domicile or may be apportioned among the various municipalities in which such bank and its branch or branches are located in the proportion which the respective amount of deposits in such branches shall bear to the total deposits of such bank and its branches, the amount of deposits to be determined as of the thirty-first of December of the preceding year. This Section shall not affect, supersede, or modify other laws upon the same subject matter, but shall be supplementary thereto, and its exercise discretionary with the banks, banking companies, firms, associations, or corporations affected hereby.