BALTIMORE (Stockpickr) -- 2%. That's how much the big S&P 500 index has move higher since the calendar flipped to 2015. If you're not careful, it would be tempting to say that stocks are "up slightly" this year. But they're not.

As the old saying goes, "It's a market of stocks, not a stock market." It's trite, but it's true.

Even though the big stock indices are up slightly year-to-date, 40% of S&P 500 components are actually down on the year right now. Put simply, it hasn't been hard to pick the wrong stocks in 2015 -- and owning the wrong names could be "toxic" for your portfolio right now.

That's why we're turning to the charts for a technical look at five big stocks to avoid (or short) in March.

Just to be clear, the companies I'm talking about today aren't exactly junk. By that, I mean they're not next up in line at bankruptcy court. But that's frankly irrelevant. From a technical analysis standpoint, sellers are shoving around these toxic stocks right now. For that reason, fundamental investors need to decide how long they're willing to take the pain if they want to hold onto these firms in the weeks and months ahead. And for investors looking to buy one of these positions, it makes sense to wait for more favorable technical conditions (and a lower share price) before piling in.

For the unfamiliar, technical analysis is a way for investors to quantify qualitative factors, such as investor psychology, based on a stock's price action and trends. Once the domain of cloistered trading teams on Wall Street, technicals can help top traders make consistently profitable trades and can aid fundamental investors in better entry and exit points.

So, without further ado, let's take a look at five "toxic stocks" you should be unloading.

Berkshire Hathaway

Up first is Berkshire Hathaway (BRK.B) - Get Report, a stock that's been a stellar performer in the past year. Since March 2014, Berkshire has rallied more than 22%, basically doubling the S&P 500's performance over that same stretch. But Berkshire is starting to show some cracks lately. Shares are perilously close to looking "toxic" this week.

Berkshire Hathaway is currently forming a descending triangle pattern, a bearish price setup that's formed by horizontal support below shares down at $145 and downtrending resistance to the upside. Basically, as Berkshire bounces between those two technically significant price levels, it's been getting squeezed closer and closer to a breakdown through our $145 price floor. When that happens, we've got a sell signal.

Relative strength, at the bottom of the chart, is an extra red flag in BRK.B. That's because our relative strength line broke its uptrend and reverted into a downtrend back in January, an indication that shares aren't just losing steam here, they're also underperforming the rest of the market. While the primary trend is still up in Berkshire, only long-term investors will want to stomach the correction that'll come from a violation of $145.

Tronox

Small-cap chemical company Tronox (TROX) - Get Report is showing traders the exact same bearish setup as the one in Berkshire this week. TROX is forming a descending triangle pattern of its own here, with support down at the $20 level. If that $20 line in the sand gets violated, then TROX becomes a sell.

Why all of the significance at $20? It's not magic. Whenever you're looking at any technical price pattern, it's critical to keep buyers and sellers in mind. Patterns such as the descending triangle are a good way to quickly describe what's going on in a stock, but they're not the reason it's tradable. Instead, it all comes down to supply and demand for Tronox's shares.

That $20 level in TROX is the spot at which there's previously been an excess of demand for shares; in other words, it's a price where buyers have been more eager to step in and buy shares at a lower price than sellers were to sell. That's what makes a breakdown below support so significant. It means that sellers are finally strong enough to absorb all of the excess demand at the at price level. If $20 gets violated, look out below.

Vodafone

$92 billion telecom stock Vodafone (VOD) - Get Report hasn't had a lot to show for the last year or so of trading. Shares have lost more than 16% of their market value over the course of the last 12 months, and while they've rebounded a bit since mid-October, this big mobile carrier is looking "toppy" as we head into March.

VOD is forming a double top, a bearish reversal pattern that looks just like it sounds. The double top is formed by a pair of swing highs that top out at approximately the same price level. The sell signal comes on a violation of the trough that separates those two peaks. For VOD, that's the $33 level.

If $33 gets violated, then $28.50 is the next meaningful support level shares are likely to test on the way down. Buyers should avoid the temptation to grab a bargain in VOD until this stock can catch a bid at support again.

AT&T

Vodafone isn't the only telco that's looking "toxic" right now. Here at home, AT&T (T) - Get Report is looking top-heavy as well. The good news is that you don't need to be an expert technical trader to figure this one out. In fact, the price action in AT&T is about as simple as it gets.

Since the summer, this stock has been bouncing its way lower in a textbook downtrending channel. The channel is formed by a pair of parallel trend lines that mark the high-probability range for shares to stay stuck within. Put simply, every test of resistance on the way down has been an opportunity to sell, and we're bouncing lower this week. The wide range in AT&T's channel means that it's doubly important to heed this bounce off of resistance.

Waiting for that bounce lower before clicking "sell" is a critical part of risk management for two big reasons: It's the spot where prices are the highest within the channel, and alternatively it's the spot where you'll get the first indication that the downtrend is ending. Remember, all trend lines do eventually break, but by actually waiting for the bounce to happen first, you're confirming that sellers are still in control before you unload shares of AT&T.

Gilead Sciences

Last up on our list of toxic trades is Gilead Sciences (GILD) - Get Report, a huge $154 billion biopharmaceutical stock that's been a stellar performer in the last year. During the trailing 12 months, Gilead has rallied 25%, more than doubling the broad market's performance over the same stretch. But traders might want to think about taking some gains off the table here.

That's because GILD is currently forming a head and shoulders top, a setup that indicates exhaustion among buyers. The setup is formed by two swing highs that top out at approximately the same level (the shoulders), separated by a higher high (the head). The sell signal comes on a move through GILD's neckline at $95. If $95 gets violated in GILD, then look out below.

Momentum is the side-indicator to watch in Gilead Sciences. 14-day RSI, our momentum gauge, made lower highs on each of the price peaks, an indication that buying pressure is seriously waning in this stock. Remember, the head and shoulders in GILD only gets invalidated on a print above its $115 high-water mark. Otherwise, keep an eye on that shaky $95 price floor.

Jonas Elmerraji, CMT, is a senior market analyst at Agora Financial in Baltimore and a contributor to

TheStreet

. Before that, he managed a portfolio of stocks for an investment advisory returned 15% in 2008. He has been featured in

Forbes

,

Investor's Business Daily

and on

CNBC.com

. Jonas holds a degree in financial economics from UMBC and the Chartered Market Technician designation. Follow Jonas on Twitter @JonasElmerraji.