DollarLink News -- December 31, 1998

$INDU and $DJ over 9600

Dow-Jones Industrials is near the 9600 price level. That causes DollarLink to stay at that level and not exceed it.

In order to be able to process $INDU and $DJ prices higher than 9600 correctly, you can use the file ACCURATE -- described in detail in the November 1996 newsletter -- which is designed to allow users to correct Dow-Jones prices when they go over 9600.

Alternatively, you could use the file REDUCE where a similar procedure can be done, however then the historical data files will be more difficult to adjust. REDUCE is better for stocks and commodities, ACCURATE is better for indices.

The file called ACCURATE contains the offsets to use for any market index (symbols that have one $ at the beginning of its name) you want. It is a small text file and you can modify it with any text editor or word processor. DollarLink reads this file at startup. If it finds a line in the form

ABCD,NN.N

then DollarLink knows to offset all prices for the index $ABCD by the amount NN.N.

If the file ACCURATE is not in the DollarLink directory, then DollarLink works as before this upgrade.

The current ACCURATE file that you should have in the DollarLink directory already has lines for $INDU and $DJ that offsets the numbers internally by 3000. To fix the current problem, replace that 3000 with 6000. In other words, you should have the lines

INDU,6000  
DJ,6000

This will offset the $INDU and $DJ internal prices by 6000.0.

Please review our newsletter for November 1996 for further details on ACCURATE and its effect on historical data.

Adjusting historical data

After you upgrade, one step remains. The upgrade will affect all historical data. Using the ACCURATE approach to keep the accuracy of a symbol involves one additinal step: if you want to see historical data for that symbol prior to the time you started using ACCURATE, you will have to modify the data because when DollarLink uses the data for display or numerical computations, it will add the offset amount and therefore old data will be too big (by the offset amount).

There are two ways to adjust the historical data, either outside of DollarLink or while running DollarLink. The two ways are described below.

However, whichever way you choose, as a precaution, you should back-up the historical data before you proceed. Simply copy it to some temporary directory. For example, to back-up daily historical data, from the DollarLink directory do the following two commands

MD  TMPCLS [enter] 
COPY  CLS  TMPCLS [enter]

Similarly for 05M, 15M, 30M, 60M subdirectories which contain 5, 15, 30 and 60 minute data files.

1. While Running DollarLink

While in text mode, place the cursor over the $INDU symbol. Then press Del and then 5 keys. DollarLink will prompt you. When asked, enter the adjustment factor as -3000.

2. Outside of DollarLink

First, run the SPLIT utility from the DollarLink directory:

SPLIT $INDU    -3000.0    date1    date2

This tells the utility to subtract 3000 from all $INDU data in all the historical files between dates date1 and date2.

If you enter 0 and 0 for date1 and date2 then ALL the files that contain $INDU data will be adjusted.

CLB files

After the SPLIT utility is done, it leaves the original files with B being the last letter of the file extension. (In other words, for example, the pre-SPLIT file 02-21-97.CLS will be now called 02-21-97.CLB and the SPLIT-adjusted file will be called 02-21-97.CLS.) After a few days of verification, you should delete all these historical files that end with a B from the disk because they take up room. To do that, from the DollarLink directory execute

DEL CLS\*.CLB [enter]

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