The annual, street pavement condition index of the unincorporated areas of Marin County. Data starts in 2003 and is updated annually. Pavement condition is measured using the Pavement Condition Index (PCI), as described below.

"Pavement condition index (PCI) relies upon a three-year moving average for regional, county, and city PCI to improve the reliability of the PCI data on an annual basis. The index ranges from 0 to 100, with 0 representing a failed road and 100 representing a brand-new facility. Segment PCI data is collected on a rolling basis but is imputed for interim years based on facility age and treatments using the MTC StreetSaver system."
Source: Metropolitan Transportation Commission Vital Signs website