Matt Krantz

USA TODAY

The bad year for stocks is getting worse by the minute - and tech investors are feeling the brunt of the pain.

The 462 information technology stocks in the broad Russell 3000 index have shredded a total of $529 billion this year thanks to their average decline of 14%, according to a USA TODAY analysis of data from S&P Capital IQ.

Crashing stocks have served up a brutal reminder why betting on speculative stocks in the technology sector is dangerous business when investors get nervous about growth. The tech-heavy Nasdaq composite index is the worst hit major index of the major ones investors watch - sliding 13% this year while the broader Standard & Poor's 500 is off just 8%.

The Nasdaq's losses from the high are starting to get nervously close to the unofficial definition of a bear market: A decline of 20% or more. The Nasdaq is down more than 16% from its highest point over the past 12 months. The S&P 500, on the other hand, is down just 11.8%.

Massive drops in technology stocks are a big reason for the Nasdaq's pain. The latest stunning example is online social networking company for professionals, LinkedIn (LNKD). After telling investors that profit would grow this year - just not as much as previously thought, shares Friday closed down $83.90, or 44%, to $108.38. That devastating drop erases $15.3 billion in market value this year.

What's even more startling, though, is that LinkedIn's massive wealth destruction this year ranks just seventh among the tech stocks in the Russell 3000. Gadget maker Apple (AAPL) is the biggest destroyed of wealth this year - chewing through $62.3 billion this year as investors brace for the company this year to morph from a growth engine to a shrinking giant. Shares of Apple Friday closed down $2.58, or 2.7%, to $94.02.

Even Alphabet (GOOGL), the online advertising giant that briefly became the most valuable company in the world this week, has been sinking. Shares are down more than 10% since the company reported blow-out quarterly profit this week. Now, the stock has wiped out $51 billion in market value this year. Shares closed down $26.27, or 3.6%, to $703.76 Friday.

LinkedIn isn't the only former tech darling that's crashing. Salesforce.com (CRM), a cloud-based provider of worker tracking systems, is cratering and wiping out $13.2 billion in shareholder value this year. The stock closed down 13%, or $8.69, to $58.51 Friday.

Tech stocks can be huge wealth creators when the economy is looking good. But if there are any questions - or even a hint of slowing growth - watch out!

BIGGEST SHAREHOLDER WEALTH DESTROYERS IN TECH

Company, Symbol, Market cap destroyed this year ($ billions), % ch. ytd

Apple, AAPL, -$62.3, -10.7%

Alphabet, GOOGL, -$51.0, -9.5%

Microsoft, MSFT, -$42.1, -9.6%

Intel, INTC, -$25.5, -15.7%

Cisco Systems, CSCO, -$21.6, -15.7%

MasterCard, MA, -$16.3, -15%

LinkedIn, LNKD, -$15.3, -51.8%

Visa, V, -$14.4, -7.7%

salesforce.com, CRM, -$13.28, -25.4%

International Business Machines, -$8.8, -6.6%

* Information technology stocks in the Russell 3000

Source: S&P Capital IQ, USA TODAY