Apple, Alphabet, Facebook, Amazon, and Microsoft make up a whopping 37 percent of the total gains in the sharemarket while the bulk of US companies are just slouching around like teenagers in a mall.

Apple, Alphabet, Facebook, Amazon, and Microsoft saw their share prices touch record highs in recent months. Other companies grew at a rate of less than one percent during the first three months of this year.

The Wall Street Journal said that this part of a trend. Digital industries such as technology, communications, media, software, finance and professional services grew 2.7 percent annually over the past 15 years.

The slowdown is concentrated in physical industries such as health care, transportation, education, manufacturing, retail where productivity grew a mere 0.7% annually over the same period.

As technology companies continue to scale, the network effects bolstering their business are strengthening. Facebook and Google accounted for over three-quarters of the growth in the digital advertising industry in 2016, leaving the rest to be divided among small fry like Twitter, Snapchat, and the entire American media industry.

Apple and Alphabet have achieved a virtual duopoly on mobile operating systems, with only a tiny sliver of consumers choosing an alternative for their smartphones and tablets.