Financial Times publication / Morgan Stanley research.
Oh.. And you know what, back in 2012 when this article was published, it wasn't just 70% of overall activity mad by computers... it was 84%...
Open you eyes... Just saying.
Also, Wave 4 CANNOT go into wave 1 area.
Elliot Waves theory was developed in the late 20's of the last century, based on the (right) assumption that human psychology creates a repeating pattern of actions in the market.
Nowadays though, it's a whole new story. approx. 70% of the actions done in the market are made by computers. No psychology involved. Only pure Technical analysis (highs, lows, trends etc.); News ; Fundamental data.
Elliot Waves theory is nice, but very outdated in my opinion. I would strongly advise you to go with some other method, but, it's only me... and I could be entirely wrong.