Creating medians per industry group in a panel data set

Dear all,

We are having some problems calculating a variable. What we would like to do is the following: the median industry book leverage.

This could be done in the following way:

1. We would like Stata to identify the different industries we have defined on the basis of sic codes
   (for example 1 industry sic 4000-4900)
   
   The full list is the following:
   (sic, "0100","0900")
   (sic, "1000","1400")
   (sic, "1500","1700")
   (sic, "2000","3999")
   (sic, "4000","4900")
   (sic, "5000","5100")
   (sic, "5200","5900")
   (sic, "7000","8900")
   (sic, "9100","9900")
2. Thereafter, we would like Stata to calculate the median of book leverage of every sic-industry group.
   
   What is the best way to do this?
   generate new variables or is there a stata shortcut?
   
   
   Thank you in advance.