(Portland, OR)  --  Gas prices are slowly dropping ahead of the Independence Day holiday weekend.  Triple-A says the national average fell nine cents to four-88 a gallon.  Oregon's average declined three cents to five-50 a gallon.  The price of crude oil fell which caused gas prices to go down.  Diesel in Oregon increased 15 cents a gallon over the last week reaching a new record high six-47 a gallon.