Shares Outstanding
The volume of stock shares issued by the company and in the hands of the public. This number entails how much is being traded in the open market. A decreasing shares outstanding over time may be the result of company buybacks. Companies frequently make stock buybacks and retire those buybacks as treasury stock.
Shares outstanding represents a company's market value spread across the amount of shares outstanding. The amount of shares outstanding is frequently used in ratios such as Earnings Per Share.