More The average American is holding too much cash in savings, and it's keeping them from building wealth. You should instead invest your excess savings in the stock market for the best returns, NerdWallet's retirement and investing specialist Arielle O'Shea recommends. The easiest way to put your savings to work is through a 401(k), which invests your money in stocks through low-cost index funds or exchange-traded funds. Sitting on a pile of cash may sound nice, but it won't get you very far...

The world's richest people call these cities home. Cedric Ribeiro / Getty New York City, London, and Tokyo are the richest cities in the world. Private wealth could be a better way to measure the strength of an economy than GDP, according to a new report. The world's total private wealth amounts to $215 trillion. Citizens of the world control about $215 trillion in private wealth, according to New World Wealth's latest report. In each of the top 10 richest cities, residents have combined...