Gas prices kept up their slow downward descent in the week ended Dec. 13, continuing a sluggish slide that started in mid-October.

The average gallon of self-serve regular in the Los Angeles area was $2.180 for the week, according to the Energy Information Administration, down from $2.214 the previous week. While the statewide average was $2.135, down from $2.192 the week earlier, it’s nearly 51 cents more than the comparable period of 2003. L.A. is 53 cents more now than it was one year prior.

Midgrade and premium gas followed a similar pattern, peaking in mid-October and falling slowly ever since.

California was the most expensive state to buy a gallon of gas in, and San Francisco edged out L.A. as the most expensive city to fill up your tank for the week ended Dec. 13.