[amibroker] afl for HHV for past 10 days

[Ding]

Hi, 

How can I get the highest price from 20 days ago to 10 days ago? eg. let's say 
today is 2/20, I want to know the highest price from 2/1-2/10. Is there an easy 
way to use HHV function for this purpose? thx

Ding