Exhibit 99.a USG CORPORATION CONSOLIDATED STATEMENT OF EARNINGS (DOLLARS IN MILLIONS EXCEPT PER SHARE DATA) (UNAUDITED) THREE MONTHS ENDED MARCH 31, 2002 -------------- Net sales $ 829 Cost of products sold 697 Selling and administrative expenses 82 Chapter 11 reorganization expenses 2 ------------ Operating profit 48 Interest expense 1 Interest income (1) Other expense, net 1 ------------ Earnings before income taxes and cumulative effect of accounting change 47 Income taxes 21 ------------ Earnings before cumulative effect of accounting change 26 Cumulative effect of accounting change for SFAS No. 142, net of income taxes (96) ------------ Net loss (70) ============ Earnings (loss) per common share: Basic and diluted before cumulative effect of accounting change 0.60 Cumulative effect of accounting change (2.22) ------------ Basic and diluted (1.62) ============ Average common shares 43,354,025 Average diluted common shares 43,354,025