Typical full sized simulation runs contain between 100 million (1e8) and 100 billion (1e11) particles. Small tests while debugging might be as small as a few thousand particles (1e4). And tests of the code might only use one or two particles.
The thing I was working on when I switched from naive O(n^2) to R-trees had half a million (5e5) particles.
The thing I was working on when I switched from naive O(n^2) to R-trees had half a million (5e5) particles.