A small number of stocks including Amazon, General Electric, Alphabet, Microsoft, and Facebook drove market gains in 2015. So reports ABC News.
This is is a substantial change from last year and 2013 when the 10 largest stocks accounted for less than 20% of market gains as measured by the S&P 500 index. During the past 30 years, a decline in the number of stocks driving investment gains has typically preceded the end of bull markets.
Read the full article from ABC News.