How many patients with a normal C-reactive protein don't have their data recorded?
normal C-reactive protein refers to CRP LIKE '+' OR CRP LIKE '-' OR CRP < 1.0; don't have data recorded refers to Description IS NULL;
SELECT COUNT(T1.ID) FROM Patient AS T1 INNER JOIN Laboratory AS T2 ON T1.ID = T2.ID WHERE (T2.CRP = '-' OR T2.CRP = '+-' OR T2.CRP < 1.0) AND T1.Description IS NULL