Real estate assessments have fallen slightly in the city, according to preliminary numbers presented Wednesday by the real estate assessor.

Values are down by an average of about 2.2 percent, Assessor Jean Jackson said, but she cautioned that the numbers are only preliminary and do not include new construction and other factors.

The decrease equals a potential loss of about $2 million in revenue, Budget and Strategic Planning Director Anne Seward said.

“I’m not sure this really surprises anybody,” Mayor Linda T. Johnson said during a work session discussion on the new numbers.

Some of the reduction is market-driven, Jackson said, and some resulted from a “clean-up” of prior assessments she has been doing since taking office.

As a percentage of assessed value, residential and agriculture properties have fallen slightly, while multifamily and commercial properties have risen.

“That’s what you want,” City Manager Selena Cuffee-Glenn said, referencing the rising commercial base and corresponding fall in residential assessments.

The city is facing a handful of lawsuits based on what the plaintiffs believe are inflated assessments in previous years. Harbour View Hotels, owner of the Hilton Garden Inn on Harbour View Boulevard, has sued the city for what it says are over-assessments for the 2011, 2012 and 2013 tax years. Ainslie Group has sued on behalf of 71 residential parcels off Pitchkettle Road for the years 2007-2011. And BSJ, LLC is seeking adjustments on 20 lots in the Governor’s Pointe Subdivision in North Suffolk for the 2013 tax year.

Jackson said Wednesday that reassessment notices will be mailed March 15. Informal hearings for those seeking changes will begin March 18. Disagreements not resolved at that step will move to Board of Equalization hearings, which will take place May 1-31.

Jackson said she would provide more detailed and finalized information at a future City Council meeting. City Chief of Staff Debbie George said Wednesday the delay is to ensure the accuracy of the information.