Carlyle Group said it expects to raise $100 billion for its funds in the next several years from investors seeking higher returns in an era of ultra-low interest rates and richly valued stocks and bonds.

The Washington, DC, private equity firm currently manages around $169 billion, up from $106.7 billion at the end of 2010. David Rubenstein, who founded the firm in 1987 with William Conway and Daniel D'Aniello, called the fundraising goal "substantial but quite realistic".