NEW YORK (AP) — Holiday sales don't seem to be picking up as it gets closer to Christmas.

After a strong start to the season, sales at stores have fallen for three consecutive weeks.

And that's putting a lot of pressure on retailers.

ShopperTrak says for the week that ended Sunday, sales at U.S. stores dropped 3.1 percent to $42.7 billion, when compared to the same period last year.