X deme's population was steady at 4109 before it grew to 5005 1470.0 generations ago, maintaining that number to the present.
time_units: generations
demes:
  - name: X
    start_time: .inf
    epochs:
      - start_size: 4109
        end_time: 1470.0
      - start_size: 5005
        end_time: 0