The U.S. advertising market had its strongest September ever, rising 8.2% over September 2018, according to the latest monthly data from Standard Media Index.

The U.S. Ad Tracker shows September 2019 reaching an index of 264, the highest ever for the month, and trailing only November, which is historically the strongest month of the year for ad demand due to incremental holiday activity.

September’s index is up 26.9% from August’s index, MediaPost reports.

Powered by Standard Media Index, the Ad Market Tracker indexes the movement of U.S. ad market volume on a month-to-month basis. Data is derived from actual spending by ad agencies, representing 70% of all U.S. agency spend.