I just added an "enter month" parameter to a Crosstab in Acccess 2000 and it produced this SQL statement

PARAMETERS [enter month] Text ( 255 );
TRANSFORM Count([8D Summary for Graphs].[Ref NO]) AS [CountOfRef NO]
SELECT Format([Open Date],"yyyy") AS [Year], [8D Summary for Graphs].DEPARTMENT, Count([8D Summary for Graphs].[Ref NO]) AS [Total Of Ref NO]
FROM [8D Summary for Graphs]
WHERE (((Format([Open Date],"mmm"))=[enter month]))
GROUP BY Format([Open Date],"yyyy"), [8D Summary for Graphs].DEPARTMENT
PIVOT Format([Open Date],"mmm") In ("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec" );


Note the Parameter at the start of the statement.