HP 10bII+ Financial Calculator (NW239AA) HP 10BII+ Financial Calculator. The HP 10bII+ is the smart choice for business and finance needs. You'll be able to work quicker and more efficiently with over 100 time-saving, easily-accessible business functions. Easily calculate loan payments, interest rates and conversions, standard deviation, percent, TVM, NPV, IRR, cash flows, and more. With so many useful features, and an affordable price, the HP 10bII adds up to a wise investment. Permitted for use on the CFP Certification Exam.