[Symptoms] Cough [URI] Common (mild to moderate, hacking) [Influenza] Common (dry cough, can be severe) [Allergy] 
Sometimes
C o m m o n
V e r y c o m m o n
S o m e t i m e s ( p o s t n a s a l d r i p )
S o m e t i m e s
U n c o m m o n
N e v e r