The FOMC primarily implements monetary policy by announcing at the end of each meeting a target range 25 basis points (1/4%) wide for its key policy rate, the overnight federal funds rate. And the market’s assessment of where the FOMC could set this target range at future meetings affects the prices of options on 3-month Eurodollar futures. This chart shows the probability implied by the prices of those options that the FOMC will raise or cut its federal funds rate target range from the current range by at least 25 basis points, on or before the next quarterly-expiration date.