US STOCKS-Wall St down 1 pct as yuan's fall fuels global growth fears
* Chinese yuan hits four-year low
* Too early to judge Chinese currency policy-NY Fed's Dudley
* Alibaba falls to all-time low after revenue growth slows
* Apple hits more than six-month low
* Indexes down: Dow 1.1 pct, S&P 1 pct, Nasdaq 1.2 pct (Updates to open)
By Tanya Agrawal
Aug 12 (Reuters) - Wall Street was down more than 1 percent for a second day in a row, with the Dow falling to a six-month low, on Wednesday as the continued dip in the yuan, exacerbating fears about a global economic slowdown.
The yuan hit a four-year low against the dollar, its weakest since August 2011, after the Chinese central bank set its daily midpoint reference at a level even weaker than Tuesday's devaluation.
A cheaper yuan reduces the competitiveness of companies outside of China as it makes their goods and services more expensive, while reducing the value of revenue they generate in the country. Continuación...