Here is the opening statement from the Department of Labor:

SEASONALLY ADJUSTED DATA

In the week ending September 19, the advance figure for seasonally adjusted initial claims was 870,000, an increase of 4,000 from the previous week's revised level. The previous week's level was revised up by 6,000 from 860,000 to 866,000. The 4-week moving average was 878,250, a decrease of 35,250 from the previous week's revised average. The previous week's average was revised up by 1,500 from 912,000 to 913,500.

The advance seasonally adjusted insured unemployment rate was 8.6 percent for the week ending September 12, a decrease of 0.1 percentage point from the previous week's revised rate. The previous week's rate was revised up by 0.1 from 8.6 to 8.7 percent. The advance number for seasonally adjusted insured unemployment during the week ending September 12 was 12,580,000, a decrease of 167,000 from the previous week's revised level. The previous week's level was revised up 119,000 from 12,628,000 to 12,747,000. The 4-week moving average was 13,040,750, a decrease of 478,000 from the previous week's revised average. The previous week's average was revised up by 29,750 from 13,489,000 to 13,518,750. [See full report]

This morning's seasonally adjusted 870K new claims, up 4K from the previous week's revised figure, was worse than the Investing.com forecast of 840K.

Here is a close look at the data over the decade (with a callout for the past year), which gives a clearer sense of the overall trend.

Unemployment Claims since 2007

As we can see, there's a good bit of volatility in this indicator, which is why the 4-week moving average (the highlighted number) is a more useful number than the weekly data. Here is the complete data series.

Unemployment Claims

The headline Unemployment Insurance data is seasonally adjusted. What does the non-seasonally adjusted data look like? See the chart below, which clearly shows the extreme volatility of the non-adjusted data (the red dots). The 4-week MA gives an indication of the recurring pattern of seasonal change (note, for example, those regular January spikes).