Rookie mistake: Younger investors get hit the hardest by Snap's big decline

Key Points
  • Snap shares plunge after reporting a $2.2 billion net loss in its first quarterly report as a public company.
  • The March 2 IPO attracted several thousand new retail clients for TD Ameritrade, with an average age nearly a decade below the usual average age.
  • The youngest Snap investors did turn more negative on the stock in the last week though, according to trading app Robinhood.
Will millennials stick with Snap stock?
Will millennials stick with Snap stock?

Professional investors, most of whom have underperformed the market the last 15 years, have a message for all the millennials who just started trading when their favorite company Snap went public: Investing isn't easy.

Snap shares got destroyed in the aftermath of the social network's first earnings report, likely hitting younger investors the most, according to data from Wall Street brokers.

When the parent of popular disappearing messaging app Snapchat began trading March 2, online trading broker TD Ameritrade said it gained 6,400 new clients with an average age of 38.

That's nearly a decade younger than the average age of retail clients trading Snap that day, TD said.

Timur Emek | Getty Images

Snap shares dropped nearly 20 percent Thursday morning after its first quarterly report as a public company on Wednesday showed net losses of $2.2 billion, due to $2 billion in expenses for stock-based compensation.

In the first quarter, TD Ameritrade said Snap was among the most-bought stocks for both millennials and all clients. Both age groups' most-sold stocks last quarter were Apple, Tesla and Facebook.

Some of the younger set did turn negative ahead of this earnings disaster. Trading app Robinhood said investors age 30 and younger were selling more Snap shares than buying over the last several weeks.

The week after its IPO, the stock was most popular on the Robinhood app, but last week fell to third place, according to the firm's data scientist, Arpan Shah.

Newer investors are getting a lesson in what happens to hot internet IPOs after they go public. History shows that internet stocks tend to drop by large amounts the day after their first quarterly report as a public company. Facebook fell 11.7 percent after its initial earnings report but has climbed more than 700 percent over the last five years to a record high this month.

Disclosure: CNBC parent NBCUniversal is an investor in Snap.