Office space utilization spiked recently, according to separate metrics that track it, published by VTS and Kastle.

Demand for office space nationwide rose 31.3% from February to March, according to the latest VTS Office Demand Index.

The index, which ranks unique new tenant tour requirements, both in-person and virtual, of office properties in core U.S. markets, jumped 15 points to 63 in March. The index came in at 46 in December and January and 48 in February.

“The sluggish start to the year left us in limbo as to whether we’d see normal levels of spring activity return," VTS CEO Nick Romito said in a statement. "Thankfully, the office leasing market had its spring awakening — and then some.”

All of the cities tracked by VTS saw office demand increase in March, with five of the seven cities reporting office demand jumps of more than 30% month-over-month. San Francisco saw the largest jump, rising 69% from February to March. Office demand in both Boston and Los Angeles was up 42% in March.

Kastle reported that its 10-city average office occupancy was 49.6% for the week ending April 19, up from 46.3% the week before. All of the cities that Kastle tracks experienced increases, with the largest jumps in Houston and New York City.

More workers come to the office on Tuesday than any other day of the workweek, according to Kastle, which tracks office utilization by studying keycard, fob and KastlePresence app access data from 2,600 buildings.

On Tuesdays, occupancy for all 10 cities is almost 60%, nearly 10 points higher than the full week's average. Unsurprisingly, Friday has the lowest occupancy, 32.7%.