YORK, Pa. (AP) ¿ York Water Co., which purifies and distributes water, said Friday a higher number of customers plus a rate increase lifted its third-quarter profit by 20 percent. Net income for the three months ended in September rose to $2.1 million, or 18 cents per share, compared with $1.7 million, or 15 cents per share, in the year-earlier period. Analysts surveyed by Thomson Reuters expected, on average, earnings per share of 19 cents. Revenue increased to $9.8 million from $8.6 million, more than the $9.6 million Wall Street expected. Besides a higher number of customers, the Pennsylvania Public Utility Commission granted the company a rate increase, effective Oct. 9, 2008. York Water, the oldest investor-owned utility in the U.S., also cut costs. The increased revenue and cost savings were partially offset by higher depreciation, pension and retirement costs, and salary and wage expense. Shares slipped in after-market trading by 8 cents to $14.02.