You are right, BTW. 
3mg/ml strength of nicotine eliquid is the same as 0.3%, not 0.03%.
Therefore 2mg/ml strength is the same as 0.2%, not 0.02%.
Another...
Percentage vs. mg nicotine strengths
	
		
			
		
		
	
			
			3mg/ml strength of nicotine eliquid is the same as 0.3%, not 0.03%.
Therefore 2mg/ml strength is the same as 0.2%, not 0.02%.
Source: Understanding Nicotine Strengths
Another...
Percentage vs. mg nicotine strengths