One year ago marked the top before a nasty December drop. Here's why 2019 is different

One year ago marked the top before a nasty December drop

Let's take a trip down memory lane.

One year ago Tuesday marked the near-term top before a steep December drop. The S&P 500 declined 16% from that early month peak to a post-Christmas bottom. The large-cap index is now up 32% from that low and hit a high of 3,154 in late November.

Back-to-back declines to begin this month have some investors wary of a repeat performance. But not Todd Gordon, founder of TradingAnalysis.com.

"You've got to keep it in mind, last year we had an October slide, November consolidation into fall through December of 2018 and then we rallied. This is nothing like that," Gordon said Tuesday on CNBC's "Trading Nation."

"We've had a sharp move straight up here into early December and we're seeing a little bit of a profit taking. It's much different than last year."

He says any further weakness will act as a buying opportunity rather than any reason for concern.

"This is just a nice 3,000 break. If we were to come back and use that level as support, come back and retest, that's absolutely fine. I am long, I will remain long and I'll add to my positions if we get that lookback at 3,000," said Gordon.

Boris Schlossberg, managing director of FX strategy at BK Asset Management, agrees that this isn't the beginning of a broader downturn, but he's still cautious until economic data firms up.

"I don't think we're going to have a waterfall like we had last year, but right now I think data is definitely going to tell the story. At this point it's all been euphoria and hope. Now we've used all the ammunition, the monetary easing, the trade deal, the stock buybacks, and now it's going to have to be actually cold hard numbers," Schlossberg said during the same segment.

Schlossberg adds that it must go beyond the consumer, which has so far propped up the market with strong employment growth and spending. Until then, the market could endure some weakness into 2020.

"It's essentially going to be a slow bleed into the end of the year. It isn't going to fall hard, but it may just simply drip down. I think we definitely take back below 3,000 before it's all over," said Schlossberg.