Mercury's location in your birth chart influences all of this! Mercury never travels more than 28 degrees from the Sun, so many people will have Mercury in the same zodiac sign as their Sun.
From Monday to Friday, the stock market remains open from 9:30 am to 4:00 pm, EST. PST time is 6:30 am to 1:00 pm.
Market price returns are calculated using the midpoint of the bid/ask spread at 4:00 pm Eastern time (or the last midpoint of the bid/ask spread prior to 4:00 pm Eastern time) from the beginning of the relevant period to the end of the relevant period.