Prime Minister Naoto Kan disclosed family assets Friday of ¥22.4 million as of his inauguration last month, the lowest amount on record.
Cabinet members started disclosing their assets in 1984.
Family assets of Kan and his 17 Cabinet members averaged ¥32.86 million when they debuted June 8, also the lowest since the present asset disclosure system, which excludes shareholdings, began in 2001.
The asset disclosure covers real estate, time deposits and securities other than equity shares, but excludes ordinary savings. Cabinet ministers are also required to disclose family possession of equity shares, cars, artworks and country club memberships, but not their value.
Kan's family assets compare with the ¥1.44 billion held by his predecessor, Yukio Hatoyama, last September when he took office after the Democratic Party of Japan's landslide victory in the Lower House election that sent the long-ruling Liberal Democratic Party packing.
Kan's real estate assets include two condominium units in Musashino, Tokyo, and land lots he took over from his father in Okayama.
Hatoyama's family assets at the time of his early-June resignation as prime minister had declined by ¥556.5 million from the September level after he paid some ¥600 million in gift taxes on misreported money from his tycoon heiress mother.
The average for the Kan Cabinet also compares with ¥140.44 million for the Hatoyama Cabinet. None of the Kan Cabinet members has more than ¥100 million in assets, although four Hatoyama Cabinet members reported assets above the level. Most of Hatoyama's ministers, however, remain in Kan's Cabinet.
Financial services minister Shozaburo Jimi, from DPJ junior coalition partner Kokumin Shinto (People's New Party), ranked top in family assets among the 18 Kan Cabinet members, with ¥72.03 million, including real estate in his hometown in Fukuoka Prefecture.