MEMPHIS, Tenn. (AP) â¿¿ Mueller Industries Inc. said Tuesday its first-quarter profit tumbled 20 percent, pulled down by a drop in sales stemming from tough comparisons to a longer prior-year period and lower raw material costs. The Memphis, Tenn.-based metal components company earned $32.6 million, or 85 cents per share, down from $40.6 million, or $1.07 per share, in the same quarter last year. Excluding one-time gains related to assets and an insurance settlement, the company said it posted an adjusted profit of 69 cents per share for the recent quarter, down from 89 cents per share last year. Revenue fell 16 percent to $577.7 million from $687.7 million. The company said that about half of the drop in revenue stemmed from an extra week of sales in the year-ago period, while the rest of the decrease resulted from lower raw material costs that were passed on to customers in the form of lower prices. Mueller did not provide a specific financial outlook for the year, but it pointed to "encouraging signs" such as a 30 percent increase in building permits in March from the year before. "Although the recovery date is uncertain, Mueller is well prepared to ramp up production when it occurs," the company said. Mueller makes copper, brass, plastic and aluminum components for use in plumbing, refrigeration and ventilation systems. The company's shares rose $1.24, or 2.8 percent, to $45.39 in afternoon trading.