The bull market's historic 10-year run is due in large part thanks to the success of a handful of high-powered stocks, Goldman Sachs calculates.
"At the company level, just ten stocks accounted for nearly 25 percent of the 10-year index return," Goldman's David Kostin wrote. "Apple shares generated a 32 percent annualized total return during the past 10 years and single-handedly accounted for 20 percentage points of the S&P 500 total return."
"Information Technology contributed 22 percent of the index-level return during the past decade," Kostin added. "Sales growth accounted for more than half of the tech earnings growth with margin expansion contributing the balance."
The data show how just a handful of stocks, a majority of which in the tech area, have dominated this past bull market. Some investors worry the bull can't keep marching on if leadership remains this concentrated.
But Kostin also highlighted financials stocks, which are responsible for 15 percent of the S&P 500's return since 2009. Energy is the only sector where the level of earnings per share actually declined over the past 10 years.
"Part of the reason for the drop in earnings per share is the high starting point for WTI oil prices," the strategist wrote. "Oil prices averaged $92/barrel during the 12 months leading up to March 2009. Fast forward, and during the past year WTI has averaged $63/barrel. In aggregate, the Energy sector accounted for just 3 percent of the index-level return."
The S&P 500 marked an intraday bottom of 666, on March 6, 2009, and posted a low close of 676 three days later.
Since then, the S&P energy sector has gained 54 percent, while stocks in the top performing sector, consumer discretionary, rose 582 percent. Technology also snapped back strongly, with a gain of 512 percent and financials rose 413 percent.
Big energy names like Exxon Mobil and Chevron were underwhelming during the past 10 years, underperforming the broader market. The S&P 500, which has returned about 400 percentage points since 2009, is well ahead of Exxon's return of about 60 percentage points and Chevron's 163 percentage points, according to FactSet statistics.
The broad market index is up 9.4 percent in 2019 but down 1.5 percent in the past 12 months.