Assuming your table is called `[t]`, and that the `Value` column has been called `Val` (`Value` is a reserved word and complicates things), you can create a view (query) with the following SQL definition:

    SELECT 
        t0.CPTY, t0.Industry, t0.Val * 100.0 / 
        (SELECT sum(t1.Val) FROM t AS t1    
          WHERE t1.CPTY = t0.CPTY) AS PerCentIndustryPerCpty
    FROM 
        t AS t0;

You can make it using the "SQL view" instead of the graphical designer for views (querys).

You get this result:

[![ViewPerCents][1]][1]

---

If you don't feel comfortable with the SQL view, this can also be done within the GUI, in two steps:

1. Create a Query named `TotalsPerCPTY` with a column named `TotalValPerCPTY` that has the `SUM`s of `Val` `GROUPed BY` `CPTY`, as shown in the following image:

[![TotalsPerCPTY Query][2]][2]

2. Create the `ViePerCents` Query by joining the `t` table together with the `TotalsPerCPTY` view, using the `CPTY` column, with one computed column that computes `Val / TotalValPerCPTY * 100.0`:

[![Final query][3]][3]


  [1]: https://i.sstatic.net/6WpF9.png
  [2]: https://i.sstatic.net/XtsAf.png
  [3]: https://i.sstatic.net/JqfZJ.png