PMI is private mortgage insurance. This insurance policy protects the lender in case the borrower defaults. This will vary, depending upon the type of loan and the down payment amount. For a 20% down payment or greater, this field will be 0. For an Insured Conventional loan, this field should be 1 (this may be lower with a great credit score).  For an FHA loan, use 1.35.  For a VA loan, use 0.