Karim writes:

Initial claims fell 21k to a 3mth low of 434k, but the Labor Dept attributed this to a missed seasonal adjustment factor due to the Columbus Day holiday

Unadjusted claims rose by 3%, or 11k; the seasonal adjustment factor was looking for a 7.8% rise. Thus, the seasonally adjusted number fell by 21k.

The spike to 475k the week before the holiday likely reflects the flipside of this.

After also adjusting for the spike that followed benefit extension in late July, claims have really been very stable in the 440-460k range for the past 6mths.