Under keyword frequency, you have the option to check every 48 hours, one week, two weeks. That means it will check once in a 48 hour period and so on and so forth.

One check is also one keyword credit depending on the type of check amount you have selected. (if you have 3 search types selected, 1 check will equal 3 credits used).

You can change the frequency by clicking into any one of your locations, and clicking the Keywords option on the left side of the screen. Next click on the checkbox next to the keyword(s) you'd like to change the frequency for, and select the option from the pop-up menu that can be seen in the image above this paragraph.