15.5% of Seattle residents moved in the last year, against 12.3% nationally. Moving is what generates junk: the garage that never got cleared, the furniture that does not fit the new place, the tenant who left half a flat behind. Across 1,608,596 households, that churn is the base load.
Renters occupy 40.0% of homes here, 5.2 points above the national 34.8%. With 1,608,596 households in the market, multifamily turnover is a standing source of scheduled work — the kind property managers call the same vendor for every month.
Seattle has 1,608,596 households across a population of 4,061,920. Junk removal demand tracks households more closely than anything else: people move, renovate, downsize and clear out, and every one of those is a job for someone with a truck and a crew.
Where these figures come from
Every number in these paragraphs is a Census figure for the Seattle metro, compared with the national figure from the same table.