I use Yahoo EOD data,and I've downloaded historical data starting in 1970. When I look at longer term charts in a weekly or monthly time frame,I get many volume bars that display a negative value.(the bars of the volume histogram are below the zero line instead of above.
If I stay in the daily time frame,and zoom out until all data is displayed,the bars will all stay in the positive,but if I then click to a weekly or monthly time frame,it will show a lot of bars below the zero line.Is this an issue with the program or with Yahoos data,and is there a way to fix it? Also,I've read that Amibroker will only display up to a certain value because that's as high a number that the program will recognize.Is there any way around this? I'm more interested in the volume relative to previous levels rather than the actual number itself. Is there a way to cut the volume in half,so the program will display the full bar? My thinking behind this is that it will display the full bar in the correct proportion to the others,and if I wanted to know the actual number,I could just double it mentally to get the real value.This is an issue with the major indices,not individual stocks,so I'd like to be able to apply this only to them and not everything in my database if it's possible. Thanks. -jim
