Note 13. Per Share Information — The following table sets forth the computation of basic and diluted net loss per common share: (In millions except per share amounts) Weighted average shares issuable upon the exercise of stock options which were antidilutive, and thus not included in the calculation, were 7.5 million in 2003, 5.9 million in 2002 and 4.5 million in 2001. Rental expense under operating leases was $17.5 million in 2003, $15.9 million in 2002 and $22.2 million in 2001. Future minimum rental commitments under operating leases with non-cancelable terms of more than one year at December 31, 2003, were as follows: $11.9 million in 2004, $11.1 million in 2005, $9.5 million in 2006, $4.8 million in 2007, $3.7 million in 2008 and $6.1 million thereafter.  When it is probable that a liability has been incurred or an asset of the Company has been impaired, a loss is recognized if the amount of the loss can be reasonably estimated. The Company is subject to various domestic and international environmental laws and regulations that govern the discharge of pollutants into the air or water, and disposal of hazardous substances, and which may require that it investigate and remediate the effects of the release or disposal of materials at sites associated with past and present operations, including sites at which the Company has been identified as a PRP under the Federal Superfund laws and comparable state laws. The Company could incur substantial cleanup costs, fines, and civil or criminal sanctions, third party property damage or personal injury claims as a result of violations or liabilities under these laws or noncompliance with environmental permits required at its facilities. The Company is currently involved in the investigation and remediation of a number of the Company’s current and former sites as well as third party sites under these laws. In accordance with the Company’s accounting policy disclosed in Note 1, environmental liabilities are recorded when the Company’s liability is probable and the costs are reasonably estimable. In many cases, however, investigations are not at a stage where the Company has been able to determine whether it is liable or, if liability is probable, to reasonably estimate the loss or range of loss, or certain components thereof. Estimates of the Company’s liability remain subject to additional uncertainties regarding the nature and extent of site contamination, the range of remediation alternatives available, evolving remediation standards, imprecise engineering evaluations and estimates of appropriate cleanup technology, methodology and cost, the extent of corrective actions that may be required, and the number, participation, and financial condition of other PRPs, as well as the extent of their responsibility for the remediation. Accordingly, the Company periodically reviews accruals as investigation and remediation of these sites proceed. As the Company receives new information, the Company expects that it will adjust its accruals to reflect the new information. Future adjustments could have a material adverse effect on the Company’s results of operations in a given period, but the Company cannot reliably predict the amounts of such future adjustments. ATI Annual Report 2003 61 Note 14. Commitments and Contingencies — Years ended December 31, 2003) 2002) 2001) Numerator: Basic and diluted net loss per common share before cumulative effect of change in accounting principle $(313.3) $(65.8) $(25.2) Cumulative effect of change in accounting principle, net of tax (1.3) —) —) Numerator for and diluted loss per common share $(314.6) $(65.8) $(25.2) Denominator: Weighted average shares 80.8) 80.6) 80.2) Contingent issuable stock ––) —) 0.1) Denominator for basic and diluted loss per common share 80.8) 80.6) 80.3) Basic and diluted net loss per common share before cumulative effect of change in accounting principle $0(3.87) $(0.82) $(0.31) Cumulative effect of change in accounting principle (0.02) —) —) Basic and diluted net loss per common share $0(3.89) $(0.82) $(0.31)