The U.S. stock market suffered its worst week (ending July 24) in months thanks to disappointing earnings results, especially from Apple (AAPL), Caterpillar (CAT) and International Business Machines (IBM) as well as a string of bleak sales or earnings outlook (read: 4 ETFs to Watch Post IBM 2Q Results).

This is especially true as total earnings for the S&P 500 companies that have reported so far are up 3.6% on an annual basis with a beat ratio of 73.3% while revenues have increased 0.9% with a beat ratio of 50.8%, as per the Zacks Industry Trend. While the beat ratios are better than the recent quarters, the earnings and revenue growth rates are much lower than Q1 and the four-quarter average.

Additionally, weak PMI data stretching from China to Europe, collapse in commodities and a fresh signs of slowdown in China have renewed worries about global economic growth, resulting in risk-off trade. An unexpected drop of 6.8% in new U.S. home sales for June, strong dollar and the potential for a rates hike sometime later in the year added to the list of woes.

In such a backdrop, the largest and ultra-popular SPDR S&P 500 (SPY - ETF report), tracking the S&P 500 with an asset base of around $$178.9 billion and average daily volume of more than 109 million shares, pulled out nearly $5 billion from its asset base last week, according to data compiled by etf.com. Meanwhile, the Dow Jones proxy – SPDR Dow Jones Industrial Average ETF (DIA - ETF report) – saw less than a billion dollar outflow (see: all the Large Cap ETFs here).

Given the huge outflows and weak fundamentals, the Dow Jones saw the worst weekly loss since January, tumbling nearly 3%. The S&P 500 and the Nasdaq Composite Index too dropped over 2%, marking the biggest weekly declines since March for both indices.

The terrible trading has spread to the equity ETF world as well with a number of products piling up huge losses in last week. Below, we have highlighted the five worst performing unleveraged funds of the week that went by. These funds are expected to continue their rough trading in the weeks ahead if the same trends persist.

First Trust ISE-Revere Natural Gas Index Fund ((FCG - ETF report)) – Down 10.8%

This product offers exposure to the U.S. stocks that derive a substantial portion of their revenues from the exploration and production of natural gas. It follows the ISE-REVERE Natural Gas Index and holds 30 stocks in its basket that are well spread out across components with none holding more than 4.44% share (read:4 Worst Performing U.S. Equity ETFs So Far in 2015).

The fund has amassed $186.5 million in its asset base while charging 60 bps in annual fees. Volume is solid with more than 883,000 shares exchanging hands per day on average. The ETF plunged 10.8% last week and has a Zacks ETF Rank of 4 or ‘Sell’ rating with a High risk outlook.

PowerShares S&P SmallCap Energy Fund ((PSCE - ETF report)) – Down 10.1%

This fund provides exposure to the energy sector of the U.S. small cap segment by tracking the S&P Small Cap 600 Capped Energy Index. It is less popular and less liquid with AUM of $40.6 million and average daily volume of about 23,000 shares. Expense ratio came in at 0.29%.

Holding 34 securities in its basket, it is concentrated on the top four firms with over 8% share each while other firms hold less than 5.9% of total assets. About 61% of the portfolio is tilted toward energy equipment and services while oil, gas and consumable fuels take the rest. PSCE shed over 10% over the past week and currently has a Zacks ETF Rank of 4 with a High risk outlook.

SPDR S&P Oil & Gas Exploration & Production ETF ((XOP - ETF report)) – Down 7.6%

This fund targets the oil exploration and production corner of the broad energy space by tracking the S&P Oil & Gas Exploration & Production Select Industry Index. XOP is one of the largest and popular funds in the energy space with AUM of $1.4 billion and expense ratio of 0.35%. It trades in heavy volume of around 9.7 million shares a day on average (read: Q2 Earnings Bring No Respite for Oil Service ETFs).

This fund provides an equal-weight exposure to 74 firms with none accounting for more than 2.03% of the total assets. The ETF was down 7.6% last week and has a Zacks ETF Rank of 3 or ‘Hold’ rating with a High risk outlook.

SPDR S&P Metals & Mining ETF ((XME - ETF report)) – Down 7.1%

The ETF follows the S&P Metals & Mining Select Industry Index offering broad exposure to the U.S. metal and mining industry. Holding 33 stocks in its basket, it uses an equal weight methodology and does not put more than 5.23% of assets in a single security. In terms of industrial exposure, steel makes up for large chunk at 45.9%, while aluminum, and diversified metals and mining round out the next two spots with double-digit allocation each.

The product has $315.9 million in AUM and trades in solid trading volumes of more than 1.9 million shares per day on average. It charges 35 bps in fees per year from investors and lost about 7.1% last week (read: Gold Mining ETFs Are Crashing).

BioShares Biotechnology Clinical Trials Fund ((BBC - ETF report)) – Down 6.8%

This ETF has a novel approach to biotechnology investing as it provides exposure to the companies that have a primary product in Phase I, II, or III of FDA trials by tracking the LifeSci Biotechnology Clinical Trials Index. Holding 91 stocks in its basket, the fund is widely spread out as each firm holds less than 1.8% share.
 
The fund has accumulated $40.5 million since its debut in December but has a higher annual fee of 85 bps per year. It trades in light volume of 31,000 shares a day and lost about 7% last week.