Data resolution problem and bias problem about ADIS16475

1. Is the data of ADIS16475 accurate with 16 bits or with 32 bits?

2. The bias of ADIS16475 is larger just after power on, and smaller after power on when the temperature is stable.Now I use the burst read mode to read the six-axis data and calculate the attitude. The inclination and roll Angle are ok, but the yaw Angle is always wrong.When I rotate 90 degrees by only about 85 degrees, why, is there a problem with burst read mode, is there a problem with data resolution, is there a problem with gyro bias?Thank you for reply.