New York Life Benefit Services Oct. 28 is unveiling a series of institutionally priced pooled investment options run by outside managers for defined benefit and defined contribution plans. The retirement investment series is designed to provide a low-cost investment alternative for medium-sized defined benefit and defined contribution plans. There will be 19 low-expense-ratio portfolios spanning diverse asset classes including cash, bonds, U.S. equities and international equities. Plan sponsors also will be able to choose either an actively or passively managed portfolio within each asset class. Among the outside managers that will run the commingled funds are Back Bay Advisors, Brinson Partners, Columbus Circle, Harris Associates, MacKay Shields, Mellon Capital Management and Wellington Management.