Ask and there is given:
http://www.886retracement.com/
And from my experience in trading:
I have this number in my Fibonacci measuring tool, why? Couple of reasons:
1.Specific gartley (to 88,6%)
2.Price clusters (especially 78,6 and 88,6 -do your research)
3.Standard HT formations
4.My formation ABCDE
http://www.trade2win.com/boards/for.../92176-harmonic-trading-my-abcde-pattern.html
There is big controversy in using this level (88,6), like many years ago, when was 78,6% Fibonacci level. But when you invest your time and look from different point of view (couple years of study), you will see the secret behind HT and this numbers.
Its like Martial Arts and Aikido, people often laughing when they see this art, but after couple of years practise's you finding the secret, Its my experience! This is because of, vibration factor, and you see, there is not so many peoples who can vibrate on this frequency (i mean specific brain wave frequency and mental). So it's hard concept for those who don't understand or misunderstand, but not anymore and never was, because you decide what kinda vibration you choose!
Another words: after some time of tuning yourself to this vibratory level...
This and other forums are for us for sharing purpose. So this is my knowledge from successful experience in martial arts and trading! Enjoy!