With Global X FTSE Greece 20 ETF $GREK down nearly 16% at the time of writing, two thoughts pop into my mind.

First, an old quote from Baron Rothschild: "The time to buy is when there's blood in the streets."

Then, I remember that time I bought Washington Mutual.

Just a quick reminder of what happened to Washington Mutual:

0911-web-subBANK

Back in 2007 I had built a stock picking model based on fundamental factors that I had found to be statistically significant identifiers of forward performance.  The problem is that the model was based on the concept of "how much are you paying for the fundamentals today" versus "what were investors willing to pay historically for these fundamentals?"  As WaMu's stock crashed, it looked like a screaming buy.

The problem was, the story had changed.  The fundamentals of 3 months ago were no longer the fundamentals of today.  And so without any sort of revision or forward estimate, my value measures were badly, badly wrong.

Lesson learned: buying the dip works until it really, really doesn't and you end up catching a falling knife.

This WaMu lesson was one of the things that got me interested in trend-following (particularly at the sector level) as a risk mitigating technique.

So what does trend following say for Greece right now?  Using Meb Faber's 10-month moving average technique and data from MSCI, we get the following chart:
Greece Linear Scale

Which is a little more legible when log-scaled...

Greece Log Scale...and tells us that despite a significant sell-off – and potentially even a capitulation – the market is still negatively trending.  That isn't to say that this isn't a significant buying opportunity, but there may be more downside to come.  And even if there isn't, this chart highlights that while a trend following technique may lag at exact bottoms, it can help us avoid significant risk environments and still capture the majority of market growth.

Corey is co-founder and Chief Investment Officer of Newfound Research, a quantitative asset manager offering a suite of separately managed accounts and mutual funds. At Newfound, Corey is responsible for portfolio management, investment research, strategy development, and communication of the firm's views to clients.

Prior to offering asset management services, Newfound licensed research from the quantitative investment models developed by Corey. At peak, this research helped steer the tactical allocation decisions for upwards of $10bn.

Corey is a frequent speaker on industry panels and contributes to ETF.com, ETF Trends, and Forbes.com’s Great Speculations blog. He was named a 2014 ETF All Star by ETF.com.

Corey holds a Master of Science in Computational Finance from Carnegie Mellon University and a Bachelor of Science in Computer Science, cum laude, from Cornell University.

You can connect with Corey on LinkedIn or Twitter.