Required a. Use Beneish's earnings manipulation model to compute the probability that Enron engaged in earnings manipulation for 1998, 1999, and 2000 b. Identify the major reasons for the changes in the probability of earnings manipulation during the three-vear period. 6.23 (p.482) Applying and Inte Beneish's Earnings Manipulation Score Days in Receivable Index (DSRI): 0.920x Gross Margin Index (GMID: 0.528 x Asset Quality Index (AQI): 0.404 x Sales Growth Index (SGI): 0.892 x Depreciation Index (DEPI): 0.115 x Selling and Administrative Index (SAI):-0.172 x Leverage Index (LVGI): -0.327x Total Accruals to Total Assets (TATA): 4.679 x Constant Value of y ng the Earnings Manipulation Model 1998 1999 2000 Notes [AR(tySalesAR(t-1)Sales(t-1)] (Sales(t-1)-Costs of Goods Sold(t-1) Sales(t-1)(Sales(t)-Costs of Goods SoldSales(t) (TA(t)-CA(t)-Security(t)-PPE(t)TAOI(TA(t-1)-CA(t-1)-Security t-1)-PPE(t-1TA(t-1)] 1 Overstate AR 1 Weaker Profitability 1 Less appro. Expense Eamings Boost DP(t-1 DP(t-1)+PPE(t-1)/ DPt DP+PPE(t)] SG&A( SalesISG&A(t-1)Sales(t-1)] (CL(t+LTD(TA(OCL(t-1)+LTD(t-1)TA(t-1)] [(Net Income ()-OCF(DITA(t) 1 Slower Depreciation