NEW YORK (TheStreet) -- Stocks were sliding before the Federal Reserve released the minutes of its July 28-29 Federal Open Market Committee meeting last Wednesday. The interpretation of the minutes was that the FOMC was more dovish than anticipated. Stocks briefly rebounded into the green as investors concluded that the Fed would not raise rates in September, and that a rate increase may be off the table until 2016.

Investors returned to sell strength mode, concluding that Federal Reserve policy had become irrelevant. Market concerns had clearly shifted to the weakening global economy, particularly in China. The popping of the equity bubble in China's Shanghai Composite was a bigger concern. The devaluation of the yuan had become the "black swan" for investors, and waves of selling resumed and accelerated on Thursday and Friday.

As a result, all five major equity averages ended the week with negative weekly chart profiles, with only the Standards & Poor's 500 not in correction territory, down 7.7% from the intraday high it set on May 20.

When 2015 began, key levels on technical charts showed significant downside risk at some point during the year. Key levels on technical charts for all of 2015 continue to be 14,557 on the Dow Jones Industrial Average, 1,558 on the S&P 500 and 3,901 on the Nasdaq Composite, 7,289 on Dow Transports and 954.08 on the Russell 2000.

The key technical levels that presented the upside potential were 19,600 on the Dow 30, 2,268 on the S&P 500 and 5,245 on the Nasdaq. The record intraday highs set in 2015 are 18,351.36 on the Dow 30 set on May 19, 2,134.7 on the S&P 500 set on May 20, and 5,231.94 on the Nasdaq set on July 20.

At midyear, these key levels remained the downside targets, but new additional levels suggested that investors shift to a sell-on-strength investment strategy from the long-standing buy-on-weakness mantra. A warning flag waving as July began was that the Dow Jones Transportation Average was in correction territory in a "death cross," where the 50-day simple moving average was declining below the 200-day simple moving average.

Let's look at the technicals for the five major averages, then analyze the must-see charts and technical levels for the SPDR Dow Jones Industrial Average ETF (DIA - Get Report), the SPDR S&P 500 ETF (SPY) and the PowerShares QQQ Trust ETF (QQQ - Get Report).

The Dow Jones Industrial Average ended last week with a close of 16,459.75, well below its 50-day and 200-day simple moving averages, in a "death cross" of 17,701.59 and 17,819.44, respectively. The Dow 30 is in correction territory, 10.3% below its record high of 18,351.36 set on May 19. The weekly chart is negative with the index below its key weekly moving average of 17,441. The downside risk is to annual levels of 15,112 and 14,557.

The Standards & Poor's 500 ended last week with a close of 1,970.9, below its 50-day and 200-day simple moving averages of 2,090.9 and 2,077.9, respectively, and nearing a "death cross" warning. The S&P 500 is 7.7% below its record high of 2,134.72 set on May 20. The weekly chart is negative with the index below its key weekly moving average of 2,068.7. The downside risk is to annual levels of 1,585.9 and 1,558.2 in play until the end of 2015.

The Nasdaq Composite ended last week with a close of 4,706, below its 50-day and 200-day simple moving averages of 5,066.54 and 4,912.33, respectively. The Nasdaq is 10.1% below its record high of 5,231.94 on July 20.

When an index declines this quickly over a four-week period, some technicians call this falling knife a popping bubble. The popping of the Shanghai Composite bubble totaled 34.8% from 5,178 on June 12 to 3,374 on July 9.

The Nasdaq has a negative weekly chart with the index below its key weekly moving average of 4,998. The downside, to an annual level of 3,901, is in play until the end of 2015.

Dow Transports ended last week with a close of 7,872.06, below its 50-day and 200-day simple moving averages of 8,268.09 and 8,708.79, which is a "death cross" formation that began on May 26. Dow Transports is in correction territory, down 15.4% from its record intraday high of 9,310.33 set on Nov. 28, 2014. Transports has a negative weekly chart with the index below its key weekly moving average of 8,218. Transports is below a key semiannual level of 8,495 with downside risk to an annual level of 7,289 until the end of 2015.

The Russell 2000 ended last week with a close of 1,156.79, below its 50-day and 200-day simple moving averages of 1,243.17 and 1,223.59, respectively. The Russell 2000 is 10.7% below its record intraday high of 1,296.00 set on June 23. The small cap index has a negative weekly chart with the index below its key weekly moving average of 1,219.97. The downside risk is to annual levels of 975.84 and 954.08.

Here's the weekly chart for the SPDR Dow Jones Industrial Average ETF, also known as Diamonds.


Courtesy of MetaStock Xenith

Diamonds had a close of $164.41 on Friday, below its 50-day and 200-day simple moving averages of $176.92 and $178.06 in a "death cross" since Aug. 12. The weekly chart is negative with the ETF below its key weekly moving average of $174.30 with a momentum reading of 24.58 down from 29.69 on Aug. 14. The record intraday high for Diamonds is $183.35 set on May 20.

The uptrend connecting the low of $64.78 set during the first week of March 2009, through the low of $103.84 set during the week off Oct. 7, 2001, comes in this week at $161.71.

The downside risks in the second half of 2015 are key technical levels of $150.82 and $145.24, which do not expire until the end of 2015. A key level on technical charts of $168.63 is for this week only.

Here's the weekly chart for the SPDR S&P 500 ETF, also known as Spiders.


Courtesy of MetaStock Xenith

Spiders had a close of $197.83 on Friday, below its 50-day and 200-day simple moving average of $209.12 and $207.85, respectively, with a possible "death cross" this week. The weekly chart is negative with the ETF below its key weekly moving average of $207.08 with a momentum reading of 47.06, down from 54.05 on Aug. 14. The record intraday high for Spiders is $213.78 set on May 20.

The uptrend connecting the low of $67.10 set during the first week of March 2009, through the low of $107.43 set during the week off Oct. 7, 2001, comes in this week at $167.28.

The downside risks in the second half of 2015 are key technical levels of $158.47 and $155.56, which do not expire until the end of 2015. A key level on technical charts of $203.68 is for this week only.

Here's the daily chart for the PowerShares QQQ Trust ETF.


Courtesy of MetaStock Xenith

PowerShares QQQ had a close of $102.40 on Friday, below its 50-day and 200-day simple moving averages of $109.98 and 106.89, respectively. The weekly chart is negative with the ETF below its key weekly moving average of $108.77 with a momentum reading of 54.49, down from 63.91 on Aug. 14. The record intraday high for the QQQ's is $114.39 set on July 20. The downside risk in the second half of 2015 is to a key level of $89.24, which does not expire until the end of 2015. The QQQ's are below a key semiannual level of $110.87 and above a key monthly level of $108.89.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.