The licensee shall provide store vats, having an aggregate capacity equal at least to half of the demand of the month in which most spirit is issued during the year. If the existing capacity at any time appears from the average of the issues, recorded during the previous three years, to be materially deficient, the licensee shall, if required by the[Excise Commissioner] [Legislative Supplement Part III dated 28.1.69.], make the necessary increase to it.
