I wish it was that simple. If you go to the Nasdaq site you will find a document which outlines all of the changes since the inception of the index in 1994/5.
Here are the # of deletions per year: 95 (as in 1995) 22 96 22 97 8 98 26 99 30 00 17 01 19 02 21 03 09 04 10 05 14 06 10 07 13 Regards --- In [email protected], "brian_z111" <[EMAIL PROTECTED]> wrote: > > > I've downloaded from Yahoo the 20-years Nasdaq shares in order to > > backtest in Amibroker, but I have now a big doubt. > > > > Are the tickers I have downloaded, ALL the tickers of the 20 years?? > > > > No. > > The Nasdaq has been subject to high turnover. > > > because I think that if sometimes some tickers fall from Nasdaq, and > > other ones go into Nasdaq, the historic backtest using the nasdaq > > tickers of today, is not realistic.. > > > > Or not? > > No, it is not realistic (especially with the Nasdaq). > > Survivor bias is not that simple - it works both ways - successful > stocks disapear due to acquistions etc. > > Is there any way to have the real Nasdaq100, with inputs and > > outputs?? > > Yes. > > There is a list of partial resources, for managing delisted stocks, > at the UKB - please search there for "delisted". > > You will also find some past discussion in this forum under "survivor > bias" or delisted - I also found some good discussion at the Elite > Traders forum using the same search. > > http://www.amibroker.org/userkb/ > > Lookunder DatabaseManagement >> DatabaseManagementResources >> > Tracking Stock Changes > > brian_z > > > --- In [email protected], "gonzagags" <gonzagags@> wrote: > > > > Hello > > I've downloaded from Yahoo the 20-years Nasdaq shares in order to > > backtest in Amibroker, but I have now a big doubt. > > > > Are the tickers I have downloaded, ALL the tickers of the 20 years?? > > > > because I think that if sometimes some tickers fall from Nasdaq, and > > other ones go into Nasdaq, the historic backtest using the nasdaq > > tickers of today, is not realistic.. > > > > Or not? Is there any way to have the real Nasdaq100, with inputs and > > outputs?? > > > > Thanks very much.. > > >
