It is easy to lose sight that corporate fundamentals are the primary driver of the stock market over the long run. Most media attention is focused on geopolitics, hand-wringing over Washington, and fluctuations in economic data. Quietly, however, U.S. companies continue to generate record profits and dividends.

The top chart plots per share earnings and dividend growth for S&P 500 companies. Through October, earnings grew 9.8% year-over-year. Dividends grew 14%. Stock investors have enjoyed rising share prices and higher streams of income.

Per share is an important distinction. Earnings growth can be diluted or amplified if share counts are rising or falling. Today, American companies are repurchasing shares at a rate of more than 3% per annum, helping to boost per share numbers. Moreover, fewer corporations are listed on U.S. stock exchanges today as companies are bought out or choose to remain private. In fact, with Wilshire 5000 index now contains just 3,698 companies, meaning fewer overall shares are available for purchase.

Like any market, stocks prices are determined by supply and demand. The ongoing reduction in the supply of shares has become a stealth tailwind for stocks.