The Dow Jones Industrial Average (INDEX: ^DJI) contains 30 of the best-known and most successful companies in the world. They build the airplanes we ride on, serve us millions of hamburgers every day, and bring us the Internet on the devices they assemble.

But while their distinct identities are often usurped by inclusion on the index, each of the Dow's components offers investors unique opportunities and exposure. With this in mind, the current article series provides a cursory update on each of the 30 stocks included on the storied index. Up today is Procter & Gamble (NYSE: PG).

As you can see in the chart below, while shares in the consumer products giant closely parallel the Dow, they have nevertheless underperformed the index year to date. Over the last nine months, they've returned 6.3% relative to the Dow's 8.8%. What gives?

PG Total Return Price Chart

PG Total Return Price data by YCharts

The answer is twofold. First, over the last five years, investors have flocked to Procter & Gamble as the prototypical defensive stock, and thereby have driven up its stock price. It pays a respectable dividend and has a rock-solid revenue stream thanks to its stable of 20-plus billion-dollar brands, everything from Tide to NyQuil to Oral-B. Since 2007, for instance, the company's stock has returned 14% compared to the Dow's negative 3% return. As a result, this year's underperformance may very well be attributable to profit-taking.

Second, the company has come under increased scrutiny for its relatively lackluster fundamental growth. Earlier this year, hedge fund manager Bill Ackman purchased a $1.8 billion stake in P&G, seeking to shake things up at the 175-year-old company. At a meeting between Ackman, P&G's chief executive officer, and two of P&G's board members, the activist investor aired his complaints. Among other things, the company's profit has declined for three straight years, and, according to The Wall Street Journal, "it has stumbled recently in areas where it has long been adept: understanding consumers, pricing products, and getting new and revamped products to market."

Foolish bottom line
Despite P&G's recent underperformance, it's still unquestionably one of the best and most stable companies on the market today. Three other companies that match this description are identified in our popular free report: "3 American Companies Set to Dominate the World." To download this free report instantly, simply click here now.