Hi Ivann,
As per the title - can you have a look? I suspect the jumps in profitability are too high for this to be correct?
Thanks,
Pawel
9 Replies
Hi Ivann,
I've retried Singapore - works like a charm. Thanks!
Re Korea - here is the link: https://pyinvesting.com/invest/results/1197b9c1795e42b2a03fe047bd9d1f22
Best regards,
Pawel
Hey Pawel,
I've fixed the issue with the Singapore stocks. Please try again.
Can you let me take a look at your korea backtest? Please paste the link here.
Thanks,
Ivan

@kk pang: for some of these stocks the prices are close to zero for a couple of years then suddenly jumps by 50X. This jump is not helpful for backtesting purposes because it is not realistic so to get rid of this jump I'm gonna delete the couple of years worth of data where the prices were close to zero.
And regarding Korea (I have this massive jump Apr-May 2013) - I did the check and there is nothing in Excel that increases the weight so dramatically. I also checked all the equities that were in the portfolio in that period and nothing had any dramatic increase.
Thanks!
Pawel
Hi Ivann,
What do you mean by discard the entire set of data before the jump? Can explain more so others can learn from it too.
Thanks for the heads up. I guess the best way to handle this would be to discard the entire set of data before the jump because it is not helpful to have a single stock jump over 50X (5000% return) in a single day. I will clean the data and get back to you.
Ivann,
First peak comes from Capital World Limited - excel shows it jumps from 3 percent of portfolio to 97% from Apr 2017 to May 2017. As far as I can find data for this - there was no such share price increase.
Second (June 2020) is Forise International Ltd - going from 5% to 50% of the portfolio in one month and here there was an actual share price increase that was 10x.
https://www.bloomberg.com/quote/FOI:SP
hi Pawel,
Seems like the first peak is in May 2017. Can you please check each stock below from the historical positions on May 2017 and see whether there are any stocks that had a huge jump during this period?
Thanks,
Ivan

Same thing happened for a similar South Korean backtest I just run. A jump of 70k% from month to month.
Thanks!
Pawel
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