diff --git a/README.md b/README.md
index 7268cf5..92e9e3a 100644
--- a/README.md
+++ b/README.md
@@ -101,6 +101,7 @@ Processor that implements tripled seeding Combinatorial Kalman Filter. This proc
 | **Parameter**                | **Description**                                                                                                           |
 |------------------------------|---------------------------------------------------------------------------------------------------------------------------|
 | RunCKF                       | Run tracking using CKF. False means stop at the seeding stage.                                                            |
+| PropagateBackward            | Run CKF outside-in.                                                             |
 | InitialTrackError_RelP       | Track error estimate, momentum component (relative).                                                                      |
 | InitialTrackError_Phi        | Track error estimate, phi (radians).                                                                                      |
 | InitialTrackError_Lambda     | Track error estimate, lambda (radians).                                                                                   |