Mad Money Mailbag: Tracking Drug Traffic

Editor's note: The following are questions received from viewers of "Mad Money," seen every day at 6 p.m. EDT on CNBC.

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Where can I find the number of prescriptions written for various drugs?

-- Rod from California

James J. Cramer: These data are tracked by IMS Health(RX Quote) and reported weekly. While some of the company's services are only available through subscription, they also are disseminated through news stories and analyst reports.

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How does an oil royalty trust work?

-- Nick from Missouri

James J. Cramer: These are Canadian energy entities that operate similar to the way REITs do in the real estate business. The trusts amass exploration assets and then pay dividends based on how much oil and natural gas they extract and sell. One thing to keep in mind is that these trust have fixed lives. As they deplete their reserves, management must either raise new funds to purchase more assets, or the stock ultimately will trend lower toward its terminal value of zero. It also should be noted that the Canadian government is currently discussing the removal of the trusts' tax-exempt status. Either way, there is generally a 15% withholding tax for U.S. investors.

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I bought Fording Canadian Coal Trust(FDG Quote) on Sept. 29. The company's press release said its latest dividend would be paid to shareholders of record on Sept. 30, but the ex-dividend was on Sept. 28. How do I know if I will I receive the payment?

-- Larry from New York

James J. Cramer: First, I own Fording shares in my charitable trust, ActionAlertsPLUS. For any dividend, you must own the stock the day before the ex-date to receive the payment. This important piece of information is never contained in the company press releases, and in many cases, neither is the ex-date itself. Instead, you usually are given the record date. Subtract two business days to figure out the ex-date and one more day to find out when you actually will qualify for the dividend. Of course, you technically can sell the stock on the ex-date and still receive the dividend, even though it usually isn't paid for another couple of weeks after that.

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You have said that you want viewers to own Commerce Bancorp(CBH Quote). I've had trouble purchasing the stock through my broker. What is the ticker symbol?

-- Jane from Tennessee

James J. Cramer: The ticker symbol of the New Jersey-based bank is CBH. It's not to be confused with Commerce Bancshares(CBSH Quote), which is headquartered in Kansas City, Mo. I own CBH shares in my charitable trust, ActionAlertsPLUS.