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Financial statements aren’t built solely on fixed numbers and historical facts. Many reported amounts rely on accounting estimates — management’s best judgments about uncertain future outcomes. Estimates are inherently subjective and can significantly affect reported results. How do external auditors evaluate whether amounts reported on financial statements seem reasonable?
Understanding management’s assumptions and data
External auditors pay close attention to accounting estimates during audit fieldwork. They review the methods and models used to create estimates, along with supporting documentation, to ensure they’re appropriate for the specific accounting requirements. In addition, auditors examine the company’s internal controls over the estimation process to ensure they’re robust and designed to prevent errors or manipulation.
For instance, they may inquire about the underlying assumptions (or inputs) used to make estimates to determine whether the inputs seem complete, accurate and relevant. Estimates based on objective inputs, such as published interest rates or percentages observed in previous reporting periods, are generally less susceptible to bias than those based on speculative, unobservable inputs. This is especially true if management lacks experience making similar estimates.
Challenging estimates and assessing bias
When testing inputs, auditors assess the accuracy, reliability and relevance of the data used. Whenever possible, auditors try to recreate management’s estimate using the same assumptions (or their own). If an auditor’s independent estimate differs substantially from what’s reported on the financial statements, the auditor will ask management to explain the discrepancy. In some cases, an external specialist, such as an appraiser or engineer, may be called in to estimate complex items.
Auditors also may conduct a “sensitivity analysis” to see if management’s estimate is reasonable. A sensitivity analysis shows how changes in key assumptions affect an estimate, helping to evaluate the risk of material misstatement.
In addition, auditors watch for signs of management bias, such as overly optimistic or conservative assumptions that could distort the financial statements. They also consider the objectivity of those involved in the estimation process, ensuring there’s no undue influence or pressure that could affect the estimate’s outcome.
Auditors also may compare past estimates to what happened after the financial statement date. The outcome of an estimate is often different from management’s preliminary estimate. Possible explanations include errors, unforeseeable subsequent events and management bias. If management’s estimates are consistently similar to actual outcomes, it adds credibility to management’s prior estimates. But if significant differences are found, the auditor may be more skeptical of management’s current estimates, necessitating the use of additional audit procedures.
Why estimates matter
Accounting estimates are a key focus area for auditors because small changes in management’s assumptions can have material effects on a company’s financial statements. Through rigorous testing, professional skepticism and independent analysis, auditors can help promote accurate, reliable financial reporting.
As audit season gets underway for calendar-year businesses, now’s a good time to review significant accounting estimates and address gaps in documentation. Taking these proactive measures can help streamline the audit process and reduce the risk of unnecessary delays. Contact us with questions or for assistance preparing for your audit.
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