After a bruising spring when air travel virtually shut down, passenger traffic has slowly come back — but only up to a point. The average number of travelers going through Seattle-Tacoma International Airport daily in the week starting July 5 increased by only 1,000, to 16,500, leaving traffic down 75% from a year ago.

The previous week also saw just a 1,000-passenger increase. That came after four weeks when the average grew by anywhere from 1,400 to 2,500.

The upshot is that while the total number of travelers coming through the airport is on the rise, the rate of increase has slowed.

Even with the most robust increase since the lockdown in March — gaining an average 2,500 additional passengers per day as the airport did during the week of June 14-20 — it would take about five months to return to the 67,100 average daily passengers at this time last year. If the week’s daily average only grows by 1,000 new passengers, it would take about 50 weeks, or nearly a year.

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