How do I check my data for errors I may have missed?

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Use Check Ticker Data in Data Manager, utilities to identify and in some cases fix bad data.

Errors are recorded in System Messages. Some errors will require a download for one or more days of data to correct the problem. Check Ticker Data can identify the following issues

Check Open, High, Low, and Close - Looks for Open and Close values not consistent with High and Low values.

Fix Open errors - If Open greater than High, sets Open to High. If Open less than Low, sets Open to Low

Check for days with no prices - Looks for days for tickers which do not have any price data.

Fix days with no prices - Looks for ticker prices which have partial prices and zeroes out those days if they have incomplete information. If the ticker , for example, has a closing price but does not have a figure for the high then the entire day will be invalid and will be zeroed out (including volume). This remote possibility can occur when a data service sends erroneous data. It is your responsibility to download the new data for the affected days from your data service.

Check for price variances greater than or equal to - Looks for day-to-day price changes greater than the percentage specified in the text box. The default minimum variance is 25%. You can change this value by typing a new entry in the text box. You may also specify a ticker price minimum or maximum for performing a variance check.

For example, if you wish to do a variance check of 45% for tickers whose price is less than or equal to $5.00 you would set the variance fields to:

Check for Price Variances
Greater Than or Equal to 45 %
For Prices <= 5.0000

Check for zero volume - Looks for days for which the tickers have no volume

Check start dates

Fix start dates - Compares actual date of first data against First Date. If actual date of first data is later than First Date, resets First Date to actual date (and reduces size of file). Also, if the ticker start date falls on a holiday, this will change the start date to the first non-holiday date in the future.

Fix Negative Prices or Volume - Looks for ticker prices which have prices or volume which are less than zero. This remote possibility can occur when a data service sends erroneous data. If negative prices are found then all the prices (including volume) for that day are set to zero. If only negative volume is found then only volume is set to zero. It is your responsibility to download the new data for the affected days from your data service.