The Call/Put Ratio (C/P Ratio) visual displays both the ratio of the current trading day's volume of call options to put options, as well as the ratio of open interest of call options to put options as of the prior trading day's close. The Call/Put Volume Ratio is calculated by dividing the day's total call volume by the day's total put volume across all contracts for a specific underlying security. The Call/Put Open Interest Ratio is calculated by dividing the total call open interest by the total put open interest as of the prior trading day's close across all contracts for a specific underlying security.
Call/Put Ratios can be used to gauge how investors feel about a particular security. Greater volume or open interest on puts than calls may indicate that investors feel bearish; more calls than puts may indicate that investors feel bullish. Seeing both the volume ratio (from current day) and the open interest ratio (from prior day) can help you assess both short- and long-term sentiment on a particular security.
Hovering on the Call/Put visual will display the specific ratio of puts to calls.