Minneapolis’s Walker Art Center is laying off 5% of its staff in an effort to cut costs without jeopardizing a major expansion of the museum, which focuses on contemporary art. Among the casualties is the Walker’s director of New Media Initiatives, a groundbreaking curatorial position which had won the museum acclaim when it was created. A Walker spokesman said that the major reason for the layoffs was the dismal performance of the museum’s endowment, which has fallen from $200 million to $145 million in the last few years.