Seattle and Portland had the lowest and third-lowest percentage of air-conditioned households among major metro areas in the United States, respectively.[150] In 2015, a U.S. Census Bureau survey found that only 33% of Seattle homes have air conditioning (A/C) units, but that number increased to 44% in the 2019 survey, likely due to the warming trend in that area.[2] The rate of air-conditioned households is even lower in British Columbia despite marked increases over the years – BC Hydro estimated that only 34% of the province's residents were using these cooling appliances,[151] while a separate analysis indicated that only 19% of Metro Vancouver's households used air conditioning in 2017.[152] For these reasons, authorities have waived restrictions related to COVID-19 for designated cooling shelters in Oregon,[153] Washington,[154] and British Columbia.[155]