Percentile intensity map with AFNI's 3dLocalstat

Cheers Neurostars!

I am trying to produce a map of voxels ranked by percentile of local intensity using AFNI’s 3dLocalstat. While the distribution of ‘hot spots’ in the output stats map look correct, the output voxel values are not in terms of percentile (e.g. voxel corresponding to 50th percentile is not 0.5). Am I forgetting to set an additional modifying flag? Any help is appreciated!

3dLocalstat -nbhd ‘SPHERE(3)’ -stat perc:1:0:0.1 -mask ma.dilate2_3.nii -prefix t2_perc3.nii sub-${subject}_T2w.nii.gz