As the Progressive Era's leading financier, J.P. Morgan's dedication to efficiency and modernization helped transform the shape of the American economy. Adrian Wooldridge characterized Morgan as America's "greatest banker". Morgan died in Rome, Italy, in his sleep in 1913 at the age of 75, leaving his fortune and business to his son, John Pierpont Morgan Jr. Biographer Ron Chernow estimated his fortune at $80 million (equivalent to $1.2 billion in 2019), a net worth which allegedly prompted John D. Rockefeller to say: "and to think, he wasn't even a rich man."