July 8, 2015, was a watershed day in the annals of investor uncertainty. Greece and Puerto Rico are unable to pay their debts; United Continental Airlines (UAL) briefly grounded its entire fleet. Chinese stock markets are in free fall. Trading on the NYSE was halted for about 3.5 hours. The Wall Street Journal’s website went dark for a few hours.

The DJIA sold off by 261 points while the NASDAQ dropped by 88 and the SPY sold down 35. Media outlets were spouting conspiracy theories while noting that the major indices had violated their 200-day simple moving averages, SMA (200).

Just six weeks ago the S&P 500 was making new all-time highs. Cash was trash. Now, even in a ZIRP (Zero Interest Rate Policy) world, publications like Barron’s are saying that ‘Cash is King.’

It is no wonder you are probably feeling a bit queasy. Check out the facts though before bailing out of your ETFs and stocks. The last two times when the SPY broke below or touched its SMA (200) a buying opportunity presented itself on both occasions.

The market got creamed on Oct. 10, 2014, pushing the SPY south of its SMA (200). It continued down for three more trading days before reversing sharply intra-day on Oct. 15th. Negative media coverage led many traders to dump everything out of fear of ‘another 2008’.

Panicky people sold when they should have been buying. Looking back, that was one of the best chances of the past few years to get into ETFs covering your favorite industry groups. 2014 finished on a good note but January, 2015, was a disaster. Stocks stumbled badly right out of the gate. They closed out the month badly. February 2, 2015 saw a morning sell-off that sent the averages, once again, below that magic 200-day moving average.

On that occasion the reversal came almost instantly. By the end of the day the SPY had begun its climb to a series of new all-time records.

Investors need to learn that moves below long-term trends signify periods when the damage has already been done. Of course, there can never be a guarantee that stocks that are down can’t get even worse. Certainly, though, it is harder to get hurt when jumping out of basement windows rather than from penthouse apartments.

Don’t just trust me on this. Check out the charts of some major industry groups to see that most of their component companies were back down to levels, based on trailing 50-day moving averages, last seen near last fall’s panic lows.

We are all human. It is entirely normal and okay to feel anxious when portfolios are getting beaten up. It is not alright, though, to act like everyone else. The best values always come when others are fearful.

To achieve great results you need to force yourself to load up when you least feel like it. Consider purchasing ETFs in the most brutalized industry groups shown above. Throw in some oil-related ETFs as well, if you dare.

Markets tend to rebound faster and more sharply than we ever dream possible. Bottoms occur when all you want to do is shield your eyes from seeing your own account balances.

The XIV ETN (XIV B+) is an inverse ETN that goes down when the VXX ETN (VXX B+) , also called the fear index, goes up. It dropped more than 10% on June 8th even though major markets declined by just 1% to 2%.

XIV closed at $37.48 pm July 8th, down from $50.10 in the third week in June. When indices turn up this one will surge higher and faster. The 25.1% two-and-a-half week decline illustrates that playing with the XIV is a high-risk proposition. It can make for an excellent short-term trading vehicle for those willing to live with ultra-high volatility.

Traders willing to bet that the Greek situation will calm down should put the Global X FTSE Greece 20 ETF (GREK C) on their watch list. The ETF is designed to track the performance of the largest-cap, publicly traded Greek companies.

If Greece replaces the euro with New Drachma, the currency translation will likely kill the value of these stocks in relation to the US dollar. That would be the point of maximum pessimism when brave investors should consider getting long GREK.

The best bargains come to those willing to step up and buy when others can no longer take the market’s short-term pain.

Depressed industry group ETFs offer outstanding value. Building portfolios with ETFs avoids the risks associated with individual stock picking. Horrible headlines tend to fade and shares recover over time. Fight your fears and buy. Your accountant and retirement balances will thank you later.

Disclosure: Long XIV