The average number of workers actually working in offices across 10 major U.S. metro markets took a dip in late July after rising steadily earlier in the month, according to a report by Kastle Systems.

On July 28, the company calculated that the 10-city average occupancy dropped to 34.3%, compared with 34.8% the week before (July 21). On July 14, occupancy came in at 34.5%, a marked increase from July 7, when it was 31%.

Kastle, which specializes in access control, calculated the averages based on an analysis of swipes in its access control systems in more than 2,600 buildings, representing about 41,000 businesses.

The late July decline correlates with rising coronavirus infection rates among unvaccinated people and the Centers for Disease Control and Prevention's change in its mask policy recommendations, both highly publicized events toward the end of the month.

The metro with the largest weekly drop was Austin, Texas, down just more than 2 percentage points to an occupancy rate of 51.4% on July 28, though it remains the city with the highest occupancy among the 10 in the report.

Houston, No. 2 for occupancy, dropped 0.9 percentage points to 50.7% occupancy the same week, while metro Los Angeles also lost 0.9 percentage points, down to 28.8% occupancy on July 28.

Other metros in the report were San Jose, California; Dallas; Washington, D.C.; Philadelphia; New York; San Francisco; and Chicago. Of those, only Chicago saw occupancy increase week-over-week on July 28, up a scant 0.1 percentage points.

Kastle also reported that compared to the 10-city average, the legal industry has been returning to the office at rates 10 percentage points higher than other businesses.

The financial services industry is also sticking with its plans to have employees come back to the office in August and September, despite the aggressive delta variant, Reuters reports. Wells Fargo has plans for a phased return to offices for its U.S. employees that would begin in September, and so far, it hasn't reversed its position.

“We are continuing to closely watch the data and will adjust as needed,” a bank spokesperson told Reuters.