Z deme's population was steady at 5948 before it increased to 7755 5883.06 generations ago, maintaining that number to the present.
time_units: generations
demes:
  - name: Z
    start_time: .inf
    epochs:
      - start_size: 5948
        end_time: 5883.06
      - start_size: 7755
        end_time: 0