Description: Formulas for changes in GAAP liabilities and liability accrual rates are shown for three assumption update methods—retrospective, prospective and immediate.

Description: In physics and engineering education, Fermi problems require solutions based on good approximate calculations with little or no actual data, involving making justified guesses and deducing bounds without using sophisticated tools. The idea of Fermi problems are of particular relevance to today's actuaries, as pricing, reserving, and financial reporting involve more and more complex stochastic components. The paper discusses some approximate solutions developed in academia in the spirit of Fermi problems.