How to use "Tally" in Mathematica?

I a computing the eigenvalues and eigenfunctions of Laplacian on a unit square. I have written it as follows:

{ℒ, ℬ} = {-Laplacian(u(x, y), {x, y}),
    DirichletCondition(u(x, y) == 0, True)};
{vals, funs} = 
  DEigensystem({ℒ, ℬ}, 
   u(x, y), {x, 0, 1}, {y, 0, 1}, 8);
vals

Therefore, I have received the list of first $8$ eigenvalues, that is, ${2pi^2, 5pi^2, 5pi^2, 8pi^2, 10pi^2, 10pi^2, 10pi^2, 10pi^2 }$.

Now I want to use "Tally" to find the multiplicity of a specific eigenvalue (for example, take the eigenvalue $5pi ^2$). I have no idea how to use "Tally" within the program (written above). Please help me. I have read the reference here, but I have no idea how to use it in case. Moreover I want to use "tally" within the program. Please help me.

Thanking in advanced.