The Operating Cost Adjustment Factors (OCAF) for 2018 were published in the November 2, 2017 Federal Register.  

These factors are used for adjusting or establishing Section 8 rents under the Multifamily Assisted Housing Reform and Affordability Act of 1997 (MAHRA), as amended, for projects assisted with Section 8 Housing Assistance Payments.  

The factors are effective February 11, 2018 and can be found at https://www.gpo.gov/fdsys/pkg/FR-2017-11-02/pdf/2017-23901.pdf