The number of individuals in deme P remained at 7478 until 3553.6648 generations ago, at which time it grew to a new stable size of 8429.
time_units: generations
demes:
  - name: P
    start_time: .inf
    epochs:
      - start_size: 7478
        end_time: 3553.6648
      - start_size: 8429
        end_time: 0