the Documentation (PDF )
NOTE: The data file contains a field at the end of each record for the
CDS Code. Each school, district total, DFG total and state total record
has a CDS code representing the county, district and school codes. The
first two digits represent the county code, the four digits following
that are the district code, and the last two digits are the school code.
990000000 indicates a DFG total or state total.