Up until 2173.98 generations ago, the count of S deme was 924. Following that period, it increased to 4188, where it has persisted until now.
time_units: generations
demes:
  - name: S
    start_time: .inf
    epochs:
      - start_size: 924
        end_time: 2173.98
      - start_size: 4188
        end_time: 0