diff --git a/src/segway_RMP400.cpp b/src/segway_RMP400.cpp
index 841831375ceceb4753e3f10167d2c6bcd0be128b..ee1951ec1ac6d9010e9a391e575f1a7d3b28e9da 100644
--- a/src/segway_RMP400.cpp
+++ b/src/segway_RMP400.cpp
@@ -92,7 +92,7 @@ operator<< (std::ostream& data, CSegwayRMP400 & segway)
     data << "Left wheel velocity: "      << segway.segways_[i]->get_left_wheel_velocity() << " m/s" << std::endl;
     data << "Right wheel velocity: "     << segway.segways_[i]->get_right_wheel_velocity() << " m/s" << std::endl;
     data << "Yaw rate: "                 << segway.segways_[i]->get_yaw_rate() << " degrees/s" << std::endl;
-    data << "Servo frames: "             << segway.segways_[i]->get_servo_frames() << " frames/s" << std::endl;
+    data << "Up time: "                  << segway.segways_[i]->get_uptime() << " s" << std::endl;
     data << "Left wheel displacement: "  << segway.segways_[i]->get_left_wheel_displacement() << " m" << std::endl;
     data << "Right wheel displacement: " << segway.segways_[i]->get_right_wheel_displacement() << " m" << std::endl;
     data << "Forward displacement: "     << segway.segways_[i]->get_forward_displacement() << " m" << std::endl;