A person possessing stock of a corporation cannot deduct from gross income any amount claimed as a loss merely on account of shrinkage in the value of such stock through fluctuation of the market or otherwise. The loss allowable in such cases is that actually suffered when the stock is disposed of. If such stock of a corporation becomes worthless, its cost or other basis may be deducted by the owner in the tax year in which the stock became worthless.
5.26 Ark. Code R. 51-424(a)(1)