623: Number of lighthouses in the United States, according to the Coast Guard, down from an inventory of nearly 1,000.

267: Number of lighthouses the Coast Guard maintains, including Chatham’s, that are deemed necessary as aids to navigation.

88: Number of lighthouses since 2000 that the General Services Administration has transferred to caretakers or historical societies as a cost-effective measure to preserve their history, because they were no longer deemed critical thanks to improved navigation technologies.

$268,000: The top dollar amount a lighthouse sold for at an auction (the bottom range is $50,000), according to a GSA spokesperson.

7: Number of lighthouses currently for sale.