Stock splits and price spikes on stocks and adding funds to your portfolio makes the charts scale unusable because is automatically scales to fit the largest fluctuation in the time periods view. Sometimes I will see what appears to be flat line before and after a stock split, when in fact, it is a strong performer.
Being able to zoom a chart (maybe when you rotate the screen) would mean that large events do not cloud one’s view of the days/weeks/months or years of data that is otherwise very useful.
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