data = RandomReal[{-1,1},{100000,2}];

data[[1;;12]]

distancesFromZero = Table[Norm[data[[i]]],{i,1,Length[data]}];

Histogram[distancesFromZero]

binData= BinCounts[distancesFromZero,{0,1,.001}] ;

annuliArea = Table[2 Pi r .001,{r,0,.999,.001}];

densities = Table[binData[[i]]/annuliArea[[i]],{i,1,Length[binData]}]//Rest;

Histogram[densities]