CAVEAT:


Several biweekly (BW) files have been changed since the 
first release in June 1992.  These include data for the 
following periods:

-BW8516 through BW8552
-BW8822
-BW8824
-BW8826

Additional errors remain in some of the monthly files.  
Specifically, M8805 and M8806 have not yet been reprocessed 
from corrected bi-weekly values (and therefore are incorrect). 
Furthermore, M8806 & M8707 are noted to be identical.