On Fri, 23 Nov 2012, Marius Hofert wrote:
Dear expeRts,
I would like to download a time series of historical data from the ticker with
symbol "ROG.VX". Interestingly, I obtain constant values (138.3 for each day
in the chosen period) although the yahoo.finance website tells me that the
time series is not at all constant. What's wrong?
require(tseries)
hq <- get.hist.quote(instrument="ROG.VX", start="2011-09-09", end="2012-03-28",
quote="Close", provider="yahoo", drop=TRUE)
plot(hq) # => constant
stopifnot(hq==138.3) # => constant 138.3
## However, under http://finance.yahoo.com/q/hp?s=ROG.VX&a=08&b=09&c=2011&d=02&e=28&f=2012&g=d&z=66&y=132
## the historical prices are not all equal to 138.3
It's true that that web page displays the prices correctly. However, if you
click on "Download to Spreadsheet" you also get the constant 138.3 prices. And
the spreadsheet functionality is what get.hist.quote() and other R interface to
Yahoo! Finance use.
Hence, you either have to process the HTML table or have to hope that Yahoo!
Finance fixes the problem. Not sure whether they have functionality to report
such problems...
Best,
Z