list number of files and total size by extension

#!/bin/bash
LC_ALL=C find . -name '?*.*' -type f -printf '%s.%f\0' |
LC_ALL=C gawk -F . -v RS='\0' '
    {
        if(NF==2) $(NF+1)=" ";
        s[$NF] += $1;
        n[$NF]++
    }
    END {
        PROCINFO["sorted_in"] = "@val_num_asc"
        for (e in s) printf "%15d %4d %s\n", s[e], n[e], e
    }' |
numfmt --to=iec-i --suffix=B