U.S. gas prices fell below $4 a gallon for the first time since March after peaking at $5.02 in June. Summary U.S. gas prices fell below $4 a gallon for the first time since March after peaking at $5.02 in June. Gas prices dropped 15 cents over the past week and 68 cents in July, according to AAA. The national average remains 25% higher than the $3.18 national average in August 2021. The continuous price decline since June may have …