Party On, Everyone -- But Remember That Dot-Com Bust?

No one's saying the party's over or anything, but the spectacle of stock indexes opening with drops of 2 or 3 percent, the way they have this week, can start you thinking about the past. The end of the dot-com bubble, for instance.

That plunge, which began early in 2001, did shut down a prolonged round of partying in the Bay Area. The story need not be repeated in detail, but yes, billions were invested and lost on can't-miss Internet-based enterprises like online grocery shopping and delivery (Webvan), pet food shopping and delivery (Pets.com), and ill-conceived or badly timed or fabulously cash-intensive search and publishing efforts too numerous to want to remember.

Again, 2016 isn't 2001. Sure, it's not hard to spot new-generation Web companies that are stumbling along after highly touted public stock offerings. Twitter, for instance, and Zynga. But the most talked-about new-wave companies, Uber and Airbnb, have stayed away from the public markets while they pile up round after round of private investment and build their valuations into the tens of billions of dollars.

What have those companies and their more established counterparts wrought?

The technology sector, old-line and new, has played such an outsize role in driving the Bay Area's economic boom that's it's spawned a series of best-selling books, Hollywood movies and even an HBO geek sitcom.

The $4,500-a-month, one-bedroom apartments? The appalling crowding on BART, sudden popularity of ferries and daily traffic gridlock? The nearly weekly appearance of hip, expensive new eateries that are instantly full? The ubiquitous microbrews, artisanal java and $6 bagels? The plague of bad fedoras? Yeah -- that all looks like part of the Bay Area that tech has built.

Part of what's fueled that tech-aided transformation, of course, is the compensation many tech employees get -- including stock options that, when exercised, may reappear in the form of cash offers on that house down the street.

That's why indications of trouble in the markets and the current ebb in stock prices for most of our local technology firms triggers a little bit of, "Hey, what's that?" A little like the first seconds of an earthquake seem to always trigger the thought, "Is this it? The big one?" Is this the market correction that turns out to be a downturn that turns out to be a collapse?

Nah. Although you wonder how much money has been taken out of people's pockets as the biggest tech companies watch their share prices slide. The decline, which for some firms began a year or more ago, has wiped out about $500 billion in market capitalization (the cumulative value of publicly traded shares) for 14 of the region's largest tech concerns.

Having been through a big one 15 years ago -- with its mass layoffs, empty office buildings and scads of suddenly orphaned Aeron chairs -- we're not anxious to see that again. Though it might be OK if the fedoras went away.

Below: Leading Bay Area tech companies and their current market capitalization compared to recent peak capitalization. Sources: Google Finance, Yahoo Finance.