In 2011, the BRFSS weighting methodology was changed. This makes data collected from 2011 forward incomparable to data collected prior to 2011. The SHIP will resume including BRFSS data in 2013, where baselines from 2011 BRFSS data will be calculated.
Data collected from survey respondents are adjusted to more accurately represent the Maryland population. This is called "weighted data." Learn more about weighted data here: http://www.marylandbrfss.org/pdf/BRFSS-Special-Report-9-12.pdf