AT&T (T 1.55%) is one of the most iconic stocks ever. The company’s history stretches all the way back to the late 1800’s, making it one of the oldest publicly traded American companies.

In addition to its long history of existence, AT&T has also paid a regular dividend for more than 30 years. It’s a decent one, too. The company’s dividend is $1.11 per share annually, spread over four quarterly payments of $0.2775 per share.

That means that, as of this writing, AT&T shares have a forward dividend yield (annual dividend payment divided by stock price) of 5.39%.

In order to calculate how many shares of AT&T stock an investor would need to generate $1,000 in dividend income, simply divide 1,000 by the annual dividend.

So, for example, here’s the formula with figures as of Sept. 4:

At a recent price of $20.59 per share, an investment of about $18,550 should generate $1,000 in dividend income over a year.

Of course, it’s important to remember that several factors could change how much income is ultimately generated.

For one, AT&T, like all public companies, could alter its dividend payouts — either up or down. In fact, in 2022, AT&T cut its dividend payout after the spinoff of its WarnerMedia assets.

Second, as the price of AT&T shares changes, so does the stock’s forward dividend yield. Therefore, if AT&T’s stock price decreases, an investor could purchase fewer shares but could still generate $1,000 (or more) in dividend income.

Income-seeking investors need to do their homework before buying dividend stocks. Remember: A company’s underlying financial health is just as important — if not more important — than the size of an expected dividend payment.