116. Notwithstanding section 97, where the aggregate of municipal and school taxes imposed on a person in respect of immoveables mentioned in that section for the municipal and school fiscal year begun in 1971 is less or greater than ten per cent of the net income of that person for his fiscal year closed in 1970, computed with account taken of subsection 2 of the said section, the following rules apply to computing the real estate tax exigible on those immoveables for a municipal and school fiscal year beginning between 1971 and 1977:(a) if less, the real estate tax exigible for such a fiscal year is computed as if the percentage mentioned in the said section equalled the percentage, to the second decimal, by which that aggregate exceeds the net income augmented cumulatively at the rate of two per cent per municipal and school fiscal year beginning after 1971, but not above ten per cent in all, except that the tax must never be less than that aggregate decreased cumulatively at the rate of twenty per cent per municipal and school fiscal year beginning after 1971; and
(b) if greater, the real estate tax exigible for such a fiscal year equals the tax otherwise exigible, or that aggregate decreased cumulatively at the rate of twenty per cent for each municipal and school fiscal year beginning after 1971, whichever is greater.