Required; found on the Inception tab. If you are renewing a lease, or leasing a used asset, and previous use of the asset has covered 75% or more of its original economic life, check the box. The lease is then operating unless the Ownership Transfer or Reasonably Certain Purchase Option boxes are checked. (This does not apply to IFRS 16, which does not permit operating leases.)
This can be determined automatically if you enter an in-service date and original economic life to cause the remaining economic life to be calculated automatically.