Benford’s Law Applied to the Audit of the Renovation of Minas Gerais International Airport

Benford Law establishes that the frequencies of the first digits of numbers in a database decrease from 1 to 9; the first digit 1 would appear in approximately 30% of the data, while first digit 9 would appear in less than 5% of these values. This paper presents a selection of tests used in the empirical literature and its main objective is to check if a general algorithm adopted for the selection of the audit sample is applicable to the budget spreadsheet of the Minas Gerais International Airport renovation. The results are compared with those found in the audit of the Federal Court of Accounts, which adopts the ABC Curve methodology for sample selection, showing that at least 86% of the total value of the identified overprice would be exposed had the new methodology been applied.