Whatever you think about Citigroup (C -0.32%) there's simply no question that it should be avoided by people that are near or already in retirement.

The reasons for this are threefold. First, the nation's third largest bank by assets is considerably more volatile than your average stock. With a beta of 2.27, the magnitude of its average fluctuation is more than twice that of the broader market.

Second, it pays a nominal dividend. Since slashing its quarterly payout to a penny during the financial crisis, Citigroup has repeatedly had its request to increase it denied by the Federal Reserve. Most recently, the central bank cited qualitative issues as the reason behind the rejection.

Finally, the valuation on Citigroup's stock is a glaring red flag. The bank trades for a nearly 30% discount to book value, and while some might see this as an opportunity, it seems more likely to be an accurate reflection of Citigroup's future prospects.

It's for these reasons that Motley Fool senior banking specialist John Maxfield concludes in the video below that Citigroup's stock doesn't belong in the average retiree's portfolio.