2. That as a consequence of said alteration there is a variation in the value of the taxpayer's assets.

The mere variation in the value of the taxpayer's assets cannot be classified as capital gain or loss if it is not accompanied by the corresponding alteration in their composition . Thus, the revaluation or loss in value of certain assets such as, for example, shares, real estate, etc ., whose ownership corresponds to the taxpayer, does not give rise to capital gain or loss for tax purposes until it materializes for the taxpayer.