Originally, deme S had a population size of 7513, which decreased to 1921 around 7095.7759 generations ago and has not changed since.
time_units: generations
demes:
  - name: S
    start_time: .inf
    epochs:
      - start_size: 7513
        end_time: 7095.7759
      - start_size: 1921
        end_time: 0