US Top Gap Ups and Downs on 9/12: ORCL, PKX, CASY, NBIX and More

Price charts sometimes have blank spaces known as gaps (up gaps and down gaps), where the price of a stock moves sharply up or down, with little or no shares traded in between. This is why the asset's chart shows a gap in the normal price pattern. Normally this occurs between the close of the market on one day and the next day's open.

For an up gap, the low price of the day must be higher than the high price of the previous day. A down gap is just the opposite of an up gap.

For example, if an unexpectedly high earnings report comes out after the market has closed for the day, a lot of buying interest will be generated overnight, leading to an imbalance between supply and demand. When the market opens the next morning, the stock price rises in response to the increased demand from buyers. If the stock price remains above the previous day's high throughout the day, then an up gap is formed.