Roughly four years after the World Health Organization declared Covid-19 a global pandemic, employees are still coming back into the office at about half the rate they were pre-March 2020.

Office occupancy was at 52.5% of pre-pandemic levels during the first week of March, according to Kastle Systems’ analysis of building access card swipes in 10 major U.S. metro areas.

That is 2.4 percentage points higher than this time last year, when average occupancy was at 50.1%. Last week's average was unchanged from the week before, and the previous two weeks were also just over 50%.

The data shows a wide breadth in occupancy depending on the day, demonstrating a solidifying appetite for mid-week work from the office. On Tuesdays, consistently the busiest days, employees were in the office at 61.7% of pre-pandemic levels last week. Fridays, the lowest trafficked day, had an average occupancy of 34.6%.

Another source of office usage data, Placer.ai, reported a larger bump in activity last week. It found that February office visits were up 18.6% year-over-year and down 31.3% from February 2020. It reports foot traffic using cell phone data.

Most major employers continue to require employees to come in at least three days a week, per JLL’s fourth-quarter office outlook. The firm reported that the average weekly attendance requirement for Fortune 100 companies was 2.96 days as of January.

But the number of employees under new mandates has been slowing since Q4. JLL expects the pace to continue to slow in the coming year as most private sector employers have already issued requirements.

Kastle's latest data shows Dallas reached a new high since the start of the pandemic last week, with occupancy rising 1.1 percentage points to 59.5%.

Austin had the highest office occupancy rate at 67.4%, while Philadelphia had the lowest at 42.3%.