ADXL 372 xyz output data variance is large

We continually read adx372 xyz data, and find the variance from each axis is vary large compared with low g sensor under 1g environment . Is it normal?

Test script:

while
do
echo -n "x: "
cat /sys/bus/iio/devices/iio:device0/in_accel_x_raw
echo -n "y: "
cat /sys/bus/iio/devices/iio:device0/in_accel_y_raw
echo -n "z: "
cat /sys/bus/iio/devices/iio:device0/in_accel_z_raw
echo "========"
sleep 1
done


Output data (Unit: 100mg)

x:-1
y:11
z:-6  

==========

x:-8
y:0   
z:10

================

x:-1
y:9
z:-15  ==> The max difference is 2.5g but test environment is 1g.