The markets have been selling off since the beginning of the year. Considering equities have been rallying strongly for most of last year, and that money managers poured money into the market at the end of the year to dress up their numbers, some reactionary sell-off was warranted. And no, it's not time to panic.
First, let's look at the 30 minute chart:
We see two strong sell-offs. The first is through the 181.31 level of support and the second is through the upper 176/lower 177 level. Both sell-offs have been strong and occurred on higher than usual volume. From peak to trough, the overall sell-off is from about 184 to 14 or a loss of almost 6%.
Above is a chart of the daily price action. Prices are now at important Fib levels as well as the 200 day EMA -- a very important technical point. The sell-off has obviously hit momentum and increased volatility (increased Bollinger Bands).
But, even if prices move below the 200 day EMA, it will most likely be the result of an overly aggressive selling instinct. While we are reading reports about traders being concerned with economic growth, remember we are seeing weaker numbers partially because of weather-related factors. Once we thaw out, I would expect a return to more consistent, positive numbers.