Could someone explain to me how this recursion work? Thanks

** I understand recursion method with 1 base case but don't understand when it 2 base case.

x = 4 and the answer is 3 but I don't know how the recursion work. I try to print out what the program is doing but still don't understand. Any help on how this recursion(Equation) work is appreciated.

Code :

public int numFibo(int x) { if(x==0) { return 0; } else if(x==1) { return 1; } else { return(numFibo(x- 1)+numFibo(x-2));