PWM output test for Rover

Hi, I tested PWM output for Rover using CUAVv5, 1.8.2 stable. I found that the mean output of throttle was between 160mv and 240mv using oscilloscope. Was this correct? The PWM_RATE is 50Hz, and the cycle is 20ms. The high level is between 1ms and 2ms, so the average should be 160mv and 330mv?