Actually they are on the way back up again. Several weeks ago regular in my area(Northern CA)was 4.25, it dropped to 4.17 and then in on day shot back up to 4.25.
It varies slightly from station to station but they all saw the same ups and downs.
Here in my part of PA prices have moved from 4 dollars a gallon back to 3.65 or a little less in some cases.