Until 63.3 generations ago, the population of deme S was 2943. At that point, it reduced to 2816, where it has stayed up to now.
time_units: generations
demes:
  - name: S
    start_time: .inf
    epochs:
      - start_size: 2943
        end_time: 63.3
      - start_size: 2816
        end_time: 0