I read some tip online and see ' Buy before the train arrive ' and ' Sell when no train is near the station '
Problem is how can I track my trains and rival's trains after some expansion?
When I have 30-40 trains on my rail ,for example.

In fact ,I don't quite get the stock market mechanic.

Right now ,
I'm selling my share before I expand. And buy it back after the expansion.
Because I see my investors always complain when I spend a lot of money on expansion.
And the share price drop ...or not going up.

Is stock market update the price every month? or yearly?

Which game is this inquiry about?

[edited for a spelling mistake]

LunaRusalka, your previous question was about RRT2, so I guess this one is too. Though I believe the answer would be the same for RRT3.

My guess is stock prices react to what happens. If we buy shares then their price rises immediately; if we sell shares then it falls. (Same if AI tycoons buy or sell, but I don't know whether they consider doing that at any time, or only once a month).

If the economy improves then prime rate falls and share prices rise; if the economy goes bad then so do share prices. This happens only at month start (or is it the previous month's end?) and I wonder if only at quarter years.

Those are just side issues. If we raise or cut the dividend, does this change share prices? We'd think it ought to, but what the shareholders really care about, it seems, is company profit, which increases every time a train arrives, and falls end of every month, because that is when expenses are charged (maintenance, fuel, salaries, etc). We can see that just by watching the company cash amount.