As the trend toward index funds for defined contribution (DC) grows, BlackRock Inc. announced Monday that it has expanded its menu of index mutual funds for defined contribution (DC) plans with the June launch of 10 new index funds.

Industry wide, it's expected that the share of DC assets in index solutions will double from 11% in 2005 to 20% by 2015, bringing the allocation closer to the percentage of indexing seen in defined benefit plans, BlackRock says.

"While indexing has long had a role in collective trust funds used by large and mega institutional DC plans, the trend toward indexing is expected to grow in the advisor-driven, small-to-mid size plan markets that have historically featured a heavier allocation to actively managed funds," according to the BlackRock release. "Increasingly, plan sponsors are recognizing that indexing offers significant benefits to DC plans of all sizes, providing a transparent, low cost and low maintenance approach to managing some or all of an investment portfolio."