8.	Income Taxes

The Company filed for a change in accounting method under the Internal Revenue Service tangible property regulations effective in 2014. Under the change in accounting method, the Company is permitted to deduct the costs of certain asset improvements that were previously being capitalized and depreciated for tax purposes as an expense on its income tax return. This ongoing deduction results in a reduction in the effective income tax rate, a net reduction in income tax expense, and a reduction in the amount of income taxes currently payable. It also results in increases to deferred tax liabilities and regulatory assets representing the appropriate book and tax basis difference on capital additions. As a result, the Company's effective tax rate was 27.0% and 34.6% for the three months ended March 31, 2017 and 2016, respectively. The effective tax rate will vary depending on the level of eligible asset improvements that are placed in service each period, which was higher during the first three months of 2017 as compared to the first three months of 2016.