Federal agencies have improved their responsiveness to the concerns of small-business owners, according to a report by the Small Business Administration's Office of the National Ombudsman.

The annual report, which grades government agencies on the timeliness, quality, and level of assistance offered to owners struggling to comply with federal regulations, gave top marks to a dozen agencies. Only Citizenship and Immigration Services received a failing grade.

In the past three years, agencies have sped up their response time to comments submitted by the ombudsman's office on behalf of business owners by 35 days, to an average 30-day turnaround. In addition, their responses had often led to faster and more effective resolutions, the report said.

"It is essential that regulatory enforcement by effective, and not excessive," Nicholas Owens, the national ombudsman and assistant administrator for regulatory enforcement fairness, said in a statement. Despite the gains, Owens said there was "still much work to be done."