In this segment of the Rule Breaker Investing podcast, Motley Fool co-founder David Gardner goes back to the very beginning of his investing days, when he was just 18 years old. And back then, getting data about a company was a far more analog, ink-on-paper affair than it is today. But more than discovering the experience of digging into earnings and profit margins, that stock purchase and what followed got him hooked on the game that is the stock market.
A transcript follows the video.

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This podcast was recorded on Sept. 21, 2016.

David Gardner: All right. Now, with all that said, the first investment that I ever made was in the summer of 1984. Since my birthday is in May, I took over that portfolio as I graduated from high school, and it was time to buy my first stock. It was Leaseway Transportation Company. Now, I'm assuming you've never heard of Leaseway, although if you're from the Cleveland, Ohio, area, you might know of Leaseway. And I'm not really clear whether Leaseway is even still in business today.

But Leaseway Transportation Company, the first thing that I think about, when I think of LTC, which was the ticker symbol back then, is I smell the smell of Value Line. Now, many of you will not have used or know what Value Line is, but back in the day -- and it's still a public company today with products that look much like the one I'm about to describe to you -- back in the day, this was the best way to find numbers -- financial statements dating back a decade or so for public companies. So it was the Value Line Investment Survey, and my father was subscribed to it.

It was a large, black tome. And each week, you would get kind of the weekly update. It would include updates on about a hundred companies or so, usually organized by industry, I think it is. And so, as the new mailing came in, the Value Line mailing, Dad would rip it open, he would pull out the previous update on those companies from 13 weeks before, rip it out of the big tome, and then put in the three-ring binder this new one in, and keep that fresh investment data flowing for himself and, as it turns out, for his sons as well.

And it was just sort of investing on paper -- how it was done back in those days -- and I can still smell the smell of the Value Line tome as I think about Leaseway Transportation, which, for me, was my first foray into the stock market. It was just a trucking company. It was a business I knew very little about. I think I'd seen [an] occasional Leaseway truck out there on the road. Maybe you will, because I think the brand might still be out there.

But it was very much a numerical exercise for me. That's the stage that I started at as an investor. It was what looked good on paper. Where were the ratios? Where were the multiples? Some combination of income statement -- you know, the revenues and earnings of a company -- and then the balance sheet. How much cash did that company have? How much debt did that company have?

And at the time -- and I think especially Dad had coached me to look at profit margins -- the pennies on every dollar that represent profit on every dollar of sales, the net profit margin. I was focused on that, and at least within its industry, which is a -- the trucking industry is a very low-margin industry -- it looked attractive. So I bought Leaseway at $26 a share, and sometime later that summer, I remember that it crested -- it might have even been in the fall or later, but it crested at $42 -- and I think I sold. And that was my first investment.

And the only lesson I want to pull away from that one is that I learned the stock market is fun. I mean, it's awfully fun to take real action with your money, put it in something whose price changes from minute to minute, and be patient with that, find something, choose this one, not that one, be choiceful about why you're buying a company, and tie your financial destiny to this thing that is outside of your own sphere of control. And to some, it might sound like gambling. To me, it never has, because what you're doing is you're taking part ownership, as I did, that brief time, for Leaseway Transportation.

But Leaseway was my first investment, and because it was a winning investment, it was a wonderful introduction to investing. We don't all have that good fortune with our first pick, and I'm about to mention a couple that didn't play out very well, but the stock market is fun. Sometimes I don't want things to get much more complicated than that. And especially if you're introducing young people in your life, or if you are a young person, remember that. It goes up most of the time. Two years out of every three, the stock market rises, and if you find a good company whose work you believe in, you're likely to do better than that.