Deme J had an initial size of 9022 until 994.33 generations ago. At that time, its population size reduced to 6477, and has remained there till current time.
time_units: generations
demes:
  - name: J
    start_time: .inf
    epochs:
      - start_size: 9022
        end_time: 994.33
      - start_size: 6477
        end_time: 0