Private housing starts in the US were estimated at a seasonally adjusted annual rate of 1.221 million dwellings in September, down from a revised 1.288 million in August. The unit matters: these figures express the pace of construction as a yearly rate. They are not a count of more than a million homes breaking ground in a single month.
The estimated 5.2% fall carried a margin of error of 11.8 percentage points in either direction. That interval includes an increase, so the comparison does not establish that the underlying pace actually fell. Single-family starts were estimated at an annual rate of 859,000.
Permits tell a different part of the story. Authorities authorised an annualised 1.400 million privately owned housing units, little changed from August. Permission makes a project possible, but work can begin much later. Comparing the two series helps distinguish what is in the pipeline from what builders have actually started.