How to get the index number of specific row in MySQL?

Question

I got the following table with this command.

select id, title, artistID, reg_count from contentnew order by reg_count

Now the index of the row "hh" is 5. How can I get this number 5?

        id  title              artistID  reg_count  
    ------  -----------------  --------  -----------
        35  cvb                      18            3
        23  vv                       11            3
        34  dfg                      17            4
        31  sdf                      15            5
        36  rty                      18            5
        16  hh                        9           12
                     --  --  --
        15  gg                        5           23
        28  asd                      14           23
        10  pp                        6           24
        17  jj                        9           34
         3  ee                        8           34
        29  zxc                      14           35
        14  ff                        5           42
        18  kk                        9           45
        30  wer                      15           45
        21  xx                       10           52
        26  mm                       13           53