Zero Downtick

In securities trading, a zero downtick is a trade that occurs at the same price as the prior trade for the same security where the last trade at a different price was higher. The higher price trade that precedes the zero downtick is a downtick. Thus, a zero downtick is not actually a downtick. The zero downtick is sometimes called a zero-minus tick. The opposite of the zero downtick is the zero uptick. For example, if six successive trades for a stock occur at $51, $50, $50, $49, $49, and $49, three of the six are a zero downtick. The three known to be a zero downtick are the third, fifth, and sixth tick. (The first trade of the six might also be a zero downtick, depending upon the price of trade before that!)