官方网站是这么说的:
1884 Dow Jones Indexes is founded.
The Dow Jones Averages, the creation of Charles Dow, appears for the first time in the "Customers' Afternoon Letter." At the time, it contained 11 stocks: nine railroads and two industrials. It was the precursor to the Dow Jones Industrial Average, which was launched in 1896.
它明确地讲DJ Indexes (注意单复数!)1884年建立, 而DJ Industrial Average 1896年发布.
另外, precursor 也不是完全是中文里的前身的意思, 尤其加to而不是of的时候.