Dow Jones Industrial index data?

Question

The high and low values In the historical prices link i.e.
http://in.finance.yahoo.com/q/hp?s=%5EDJI
is about 40 points more and less than data which appears in the daily chart i.e.
http://in.finance.yahoo.com/q/bc?s=%5EDJI&t=1d&l=on&z=m&q=c&c=

Please explain the reason for adjustment.
Thanx.

Answer 1

There are multiple Dow Jones Industrial Averages.

One is the Dow Jones Industrial Average Actual which uses tick (intraday) data of each of the constituents to determine the highs and lows of the index.

The other is the Dow Jones Industrial Average Theoretical which assumes that all constituent stocks made a high and low at the same point during the day.

The "Actual" average was only calculated from about the 1980s onwards whereas the theoretical has been calculated for a long time.

Unfortunately most charting/data vendors don't differentiate between the two making it rather confusing. Adding to this confusion, Yahoo uses different data sources for intraday and end-of-day data therefore mixing up the definitions in the same symbol!

Cheers,
Richard.

Answer 2

The only reason that I can think of is that the Historical Data takes the average of all the highs and the average of all the lows to compute the High & the Low -- while the bar chart looks at the tick-by-tick changes of the index.

The latter would be the correct way. You may want to check Yahoo's historical data with data from other sources.

Answer 3

check this source
www.premiumdata.net