ui-grid grouping: ordering by aggregated value

Let's say i have array of people:

[
  {name: 'Vasily', age: 18, salary: 5},
  {name: 'Vasily', age: 25, salary: 10},
  {name: 'Vasily', age: 30, salary: 15},
  {name: 'Ivan'  , age: 18, salary: 6},
  {name: 'Ivan'  , age: 25, salary: 9},
  .......
]

Each person has several rows in this array showing their salaries in different moments of life.

I want to group by name and aggregate salary and then sort by that aggregated salary. So that if i sort by aggregated salary descending i could see who earned more.

Here is plunker with what i got at this moment. This sorts by salary inside each group and i want to sort by salary globally.

Finally i found out the way. I had to use ui-tree-view instead. Here is the plunker