Delaware News Journal Delaware had the highest foreclosure rate in the country this year, according to a nationwide realty data analysis. One in every 1,705 housing units in Delaware had a foreclosure filing in the first quarter of 2021, according to the report from ATTOM Data Solutions. Of the state's three counties, Kent County saw the highest foreclosure rate at the start of this year, with one in every 1,281 housing units seeing a foreclosure filing. New Castle County saw one in every 1,691 and Sussex County saw one in every 2,094. While the First State ranked first in terms of its foreclosure rate this past quarter, it was 31st in the total number of foreclosure filings, according to the data.