The move will save the company about $450 million a year, Anadarko Chief Executive Al Walker said. The company’s stock, down more than half over the past 12 months, fell nearly 6% Tuesday to $37.65. Anadarko, one of the largest independent oil and gas producers in the U.S., reported a wider fourth-quarter loss as revenue dropped 35%. And last week, Standard & Poor’s Ratings Services changed its outlook on Anadarko’s ratings to negative, indicating a possible downgrade. Anadarko’s first reduced dividend will be made on March 23 to stockholders of record at the close of business on March 9.