Calculate the differences of the paper number with the journal name of IWC in 2000 and 2010.
"IWC" is the ShortName of journal;  '2000' and '2010' are Year;  Difference = Subtract(Count(Paper.Id(Year = 2000)), Count(Paper.Id(Year = 2010)))
SELECT SUM(CASE WHEN T2.Year = 2000 THEN 1 ELSE 0 END) - SUM(CASE WHEN T2.Year = 2010 THEN 1 ELSE 0 END) AS DIFF FROM Journal AS T1 INNER JOIN Paper AS T2 ON T1.Id = T2.JournalId WHERE T1.ShortName = 'IWC'