Mercury
Mercury signifies trade, communication, contracts and technology; its retrograde is the best-known in market folklore.
Meaning
Mercury is the messenger: commerce, short-term trading, information, data and technology. It is never more than about 28 degrees from the Sun, so it is often combust.
In market readings
Mercury retrograde, three or four times a year, is read as a period of crossed wires, revisions and second thoughts, especially around deals and communication. Its station days are the ones the tradition marks most.