Procurement Fraud Detection and Prevention November 11, 2008 Mike Blakley Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Joint meeting of RDU IIA and ISACA November 11, 2008, Capitol Club, Raleigh, North Carolina SlideSlide 1 <#> Session objectives 1. Current trends, techniques and best practices 2. Understand statistical basis for analysis 3. Procurement cards (pcards) 4. Understand use of Excel Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 2 Top Six Indicators That you might have a fraud • 6. System designed to do “three way match”, but only does two way • 5. Procurement software system doesn’t do a match • 4. When auditors ask to help them out, they point to the door • 3. No procurement software system • 2. Procurement clerk drives a Porsche • 1. Clerk’s kids drive Porsches between mountain home and beach home Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 3 Overview • Fraud patterns detectable with digital analysis • Basis for digital analysis approach • Usage examples • Using Excel Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 4 Objective 1 The Why and How • • • • • Two brief examples IIA Guidance Paper Auditors “Top 10” Process Overview Who, What, Why, When & Where Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 5 Example 1 Objective 1 School Bus Transportation Fraud • Supplier Kickback – School Bus parts • $5 million • Jail sentences • Period of years Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 6 Objective 1 Regression Analysis • Stepwise to find relationships – Forwards – Backwards • Intervals – Confidence – Prediction Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 7 Objective 1 Data outliers • Sometimes an “out and out Liar” • But how do you detect it? Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 8 Objective 1 Data Outliers • Plot transportation costs vs. number of buses • “Drill down” on costs – Preventive maintenance – Fuel – Inspection Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 9 Scatter plot with prediction and confidence intervals Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 10 Objective 1 Medicare HIV Infusion Costs • CMS Report for 2005 • South Florida - $2.2 Billion • Rest of the country combined - $.1 Billion Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 11 Objective 1 Pareto Chart Medicare HIV Infusion Costs - 2005 ($Billions) data source: HHS CMS 120.0% Annual Medicare Costs 100.0% 80.0% Pct 60.0% Cum Pct 40.0% 20.0% 15 13 11 9 7 5 3 1 0.0% County Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 12 Objective 1 Guidance Paper • A proposed implementation approach • “Managing the Business Risk of Fraud: A Practical Guide” http://tinyurl.com/3ldfza • Five Principles • Fraud Detection • Coordinated Investigation Approach Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 13 Objective 1 Managing the Business Risk of Fraud: A Practical Guide • IIA, AICPA and ACFE • Report issued 5/2008 • Section 5 – Fraud Detection Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 14 Objective 1 Section 5 – Fraud Detection • Detective Controls • Process Controls • Anonymous Reporting • Internal Auditing • Proactive Fraud Detection Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 15 Objective 1 Proactive Fraud Detection • Data Analysis to identify: –Anomalies –Trends –Risk indicators Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 16 Objective 1 Specific Examples Cited • Journal entries – suspicious transactions • Identification of relationships • Benford’s Law • Continuous monitoring Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 17 Objective 1 Data Analysis enhances ability to detect fraud • Identify hidden relationships • Identify suspicious transactions • Assess effectiveness of internal controls • Monitor fraud threats • Analyze millions of transactions Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 18 Peeling the Onion Objective 1c Fraud Items Possible Error Conditions Population as Whole Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 19 Objective 1d Fraud Pattern Detection Round Numbers Market Basket Benford’s Law Stratification Gaps Target Group Trend Line Univariate Duplicates Holiday Day of Week Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 20 Objective 1e Who Uses Analytics • Traditionally, IT specialists • With appropriate tools, audit generalists (CAATs) • Growing trend of business analytics • Essential component of continuous monitoring Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 21 Objective 1e Analytics – what is it? • Using software to: – Classify – Quantify – Compare • Both numeric and nonnumeric data Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 22 Objective 1e How - Assessing fraud risk • Basis is quantification • Software can do the “leg work” • Statistical measures of difference – Chi square – Kolmogorov-Smirnov – D-statistic • Specific approaches Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 23 Objective 1e Why - Advantages • • • • • • • • Automated process Handle large data populations Objective, quantifiable metrics Can be part of continuous monitoring Can produce useful business analytics 100% testing is possible Quantify risk Repeatable process Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 24 Objective 1e Why - Disadvantages • Costly (time and software costs) • Learning curve • Requires specialized knowledge Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 25 Objective 1e When to Use Analytics • Traditional – intermittent (one off) • Trend is to use it as often as possible • Continuous monitoring • Scheduled processing Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 26 Objective 1e Where Is It Applicable? • Any organization with data in digital format, and especially if: – Volumes are large – Data structures are complex – Potential for fraud exists Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 27 Objective 1 Summarized • • • • Objective 1 Two brief examples IIA Guidance Paper “Top 10” Metrics Process Overview Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 28 Objective 1 - Summarized 1. Understand why and how 2. Understand statistical basis for quantifying differences 3. Identify ten general tools and techniques Next is the basis … Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 29 Objective 2 Basis for Pattern Detection • Analytical review • Isolate the “significant few” • Detection of errors • Quantified approach Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 30 Objective Objective 2 3 Trapping anomalies Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 31 Objective 2 Understanding the Basis • • • • Quantified Approach Population vs. Groups Measuring the Difference Stat 101 – Counts, Totals, Chi Square and K-S • The metrics used Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 32 Objective 2a Quantified Approach • Based on measureable differences • Population vs. Group • “Shotgun” technique Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 33 Objective 2a Detection of Fraud Characteristics • Something is different than expected Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 34 Objective 2b Fraud patterns • Common theme – “something is different” • Groups • Group pattern is different than overall population Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 35 Objective 2c Measurement Basis •Transaction counts •Transaction amounts Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 36 Objective 2d How is digital analysis done? • Comparison of group with population as a whole • Can be based on either counts or amounts • Difference is measured • Groups can then be ranked using a selected measure • High difference = possible error/fraud Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 37 Objective 2d Histograms • Attributes tallied and categorized into “bins” • Counts or sums of amounts Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 38 Objective 2d Two histograms obtained • Population and group Population 700 Group 80 70 60 50 40 30 20 10 0 600 500 400 300 200 100 0 Jan- Feb- Mar- Apr- May- Jun- Jul- Aug- Sep- Oct- Nov- Dec07 07 07 07 07 07 07 07 07 07 07 07 Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Jan- Feb- Mar- Apr- May- Jun- Jul- Aug- Sep- Oct- Nov- Dec07 07 07 07 07 07 07 07 07 07 07 07 Slide 39 Objective 2d Compute Cumulative Amount for each Count by Month Cum Pct 80 120.0% 70 100.0% 60 Count 50 80.0% 40 60.0% 30 20 40.0% 10 20.0% Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC ov -0 7 N Se p07 Ju l-0 7 07 M ay - 07 M ar - Month 0.0% Ja n07 Ja n0 Fe 7 bM 07 ar -0 Ap 7 r-0 M 7 ay -0 Ju 7 n0 Ju 7 l-0 Au 7 g0 Se 7 p0 O 7 ct07 No v0 De 7 c07 0 Slide 40 Objective 2d Are the histograms different? • Two statistical measures of difference • Chi Squared (counts) • K-S (distribution) • Both yield a difference metric Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 41 Objective 2d Chi Squared • Classic test on data in a table • Answers the question – are the rows/columns different • Some limitations on when it can be applied Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 42 Objective 2d Chi Squared • Table of Counts • Degrees of Freedom • Chi Squared Value • P-statistic • Computationally intensive Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 43 Objective 2d Kolmogorov-Smirnov • Two Russian mathematicians • Comparison of distributions • Metric is the “d-statistic” Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 44 Objective 2d How is K-S test done? • Four step process 1. For each cluster element determine percentage 2. Then calculate cumulative percentage 3. Compare the differences in cumulative percentages 4. Identify the largest difference Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 45 Objective 2d - KS Kolmogorov-Smirnov Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 46 Objective 2e Classification by metrics • • • • • • • • • • Stratification Day of week Happens on holiday Round numbers Variability Benford’s Law Trend lines Relationships (market basket) Gaps Duplicates Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 47 Objective 3 Fraud Pattern Detection Round Numbers Market Basket Benford’s Law Stratification Gaps Target Group Trend Line Univariate Duplicates Holiday Day of Week Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 48 Objective 2 What can be detected • Made up numbers – e.g. falsified inventory counts, tax return schedules Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 49 Objective 2 Benford’s Law using Excel • Basic formula is “=log(1+(1/N))” • Workbook with formulae available at http://tinyurl.com/4vmcfs • Obtain leading digits using “Left” function, e.g. left(Cell,1) Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 50 Made up numbers • • • • • • Benford’s Law Check Chi Square and d-statistic First 1,2,3 digits Last 1,2 digits Second digit Sources for more info Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 51 How is it done? Objective 2 • Decide type of test – (first 1-3 digits, last 1-2 digit etc) • For each group, count number of observations for each digit pattern • Prepare histogram • Based on total count, compute expected values • For the group, compute Chi Square and d-stat • Sort descending by metric (chi square/d-stat) Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 52 Objective 2 Invoice Amounts tested with Benford’s law - Example Results Store Hi Digit Chi Sq D-stat 324 79 5,234 0.9802 563 89 4,735 0.97023 432 23 476 0.321 217 74 312 0.2189 During tests of invoices by store, two stores, 324 and 563 have significantly more differences than any other store as measured by Benford’s Law. Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 53 Next Metric 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Objective 2 Outliers Stratification Day of Week Round Numbers Made Up Numbers Market basket Trends Gaps Duplicates Dates Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 54 Objective 2 Duplicates Why is there more than one? Same, Same, Same, and Same, Same, Different Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 55 Objective 2 Two types of (related) tests • Same items – same vendor, same invoice number, same invoice date, same amount • Different items – same employee name, same city, different social security number Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 56 Objective 2 Duplicate Payments • High payback area • “Fuzzy” logic • Overriding software controls Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 57 Fuzzy matching withObjective 2 software • • • • Levenshtein distance Soundex “Like” clause in SQL Regular expression testing in SQL • Vendor/employee situations Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Russian physicist Slide 58 How is it done? Objective 2 • First, sort file in sequence for testing • Compare items in consecutive rows • Extract exceptions for follow-up Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 59 Objective 2 Possible Duplicates - Example Results Vendor Invoice Date Invoice Amount Count 10245 6/15/2007 3,544.78 4 10245 8/31/2007 2,010.37 2 17546 2/12/2007 1,500.00 2 Five invoices may be duplicates. Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 60 Next Metric 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Objective 2 Outliers Stratification Day of Week Round Numbers Made Up Numbers Market basket Trends Gaps Duplicates Dates Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 61 Objective 2 Holiday Date Testing • Red Flag indicator Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 62 Objective 2 Typical audit areas • Invoices • Receiving reports • Purchase orders Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 63 Objective 2 Federal Holidays • Established by Law • Ten dates • Specific date (unless weekend), OR • Floating holiday Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 64 Objective 2 Understanding the Basis • • • • • Quantified Approach Population vs. Groups Measuring the Difference Stat 101 – Counts, Totals, Chi Square and K-S The metrics used Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 65 Objective 2 Objective 2 - Summarized 1. Understand why and how 2. Understand statistical basis for quantifying differences 3. Procurement cards 4. Understand examples done using Excel Next up: p-cards … Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 66 Testing Procurement Card Transactions 1. 2. 3. 4. 5. Objective 3 Understand Merchant Charge Codes (MCC) Understand common policies Test procurement card transactions contained on worksheets using VBA Ability to test procurement card transactions in a file using VBA Perform an audit of procurement card transactions in a more efficient and effective manner using the concepts and techniques presented Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 67 Audit Benefits Objective 3 (How this test supports the audit) • Test compliance with policy on an account by account basis • Test compliance with policies on account limits • Enable 100% testing of transactions • Audit process which can be tailored for policy changes • Repeatable audit process Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 68 MCC Structure • • • • • Objective 3 Major Categories Airlines 30XX – 32XX Car Rental 33XX, 34XX Hotels 35XX – 37XX All Other Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 69 Policy Structure Objective 3 • Prohibited Codes • Codes allowed with a monthly limit • Codes allowed without limit • Overall card limit Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 70 Summary and Wrap Up Objective 3 1. Understand Merchant Charge Codes (MCC) 2. Understand common policies 3. Test procurement card transactions contained on worksheets using VBA 4. Ability to test procurement card transactions in a file using VBA 5. Perform an audit of procurement card transactions in a more efficient and effective manner using the concepts and techniques Joint meeting of the RDU IIA and ISACA chapters presented November 11, 2008, Capitol Club, Raleigh, NC Slide 71 Objective 3 - Summarized 1. Understand why and how 2. Understand statistical basis for quantifying differences 3. Procurement cards 4. Understand examples done using Excel Next up: Excel … Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 72 Objective 4 Use of Excel • • • • Built-in functions Add-ins Macros Database access Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 73 Objective 4 Excel – Univariate statistics • Work with Ranges • =sum, =average, =stdevp • =largest(Range,1), =smallest(Range,1) • =min, =max, =count • Tools | Data Analysis | Descriptive Statistics Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 74 Excel Histograms Objective 4 • Tools | Data Analysis | Histogram • Bin Range • Data Range Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 75 Excel Gaps testing Objective 4 • Sort by sequential value • =if(thiscell-lastcell <> 1,thiscell-lastcell,0) • Copy/paste special • Sort Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 76 Objective 4 Detecting duplicates with Excel • Sort by sort values • =if testing • =if(=and(thiscell=l astcell, etc.)) Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 77 Objective 4 Performing audit tests with macros • Repeatable process • Audit standardization • Learning curve • Streamlining of tests • Examples http://tinyurl.com/576tp8 Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 78 Use of Excel • • • Objective 4 Built-in functions Add-ins Macros Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 79 Objective 4 - Summarized 1. 2. 3. 4. Understand why and how Understand statistical basis for quantifying differences Identify ten general tools and techniques Understand examples done using Excel Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 80 Questions? Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 81 Links for more information • Kolmogorov-Smirnov • http://tinyurl.com/y49sec • Benford’s Law http://tinyurl.com/3qapzu • Chi Square tests http://tinyurl.com/43nkdh • Continuous monitoring http://tinyurl.com/3pltdl Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 82 Excel macros used in auditing • Excel as an audit software http://tinyurl.com/6h3ye7 • Selected macros http://tinyurl.com/576tp8 • Spreadsheets forever http://tinyurl.com/5ppl7t Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 83 Contact info • E-mail: Mike.Blakley@ezrstats.com • Web: http://ezrstats.com Joint meeting of the RDU IIA and ISACA chapters November 11, 2008, Capitol Club, Raleigh, NC Slide 84