she could have stayed on as a governor until 2024. instead, she'll leave next year when her successor as fed chief is sworn in. jerome powell is nominated to replace her at the top of the fed. yellen is the first fed chair in three decades not to receive a second term. forget venmo, cash is still king. it's true, digital payments have multiplied in recent years, but u.s. cash in circulation has risen nearly 90% in the last decade, according to a federal reserve study. in total $1.6 trillion in u.s. dollars exist and the majority is actually held outside the country. >> makes sense. uber plans to buy up to 24,000 self-driving cars from volvo beginning in 2019. if the nonbinding deal goes through, it would be volvo's biggest sale of autonomous cars yet. uber's self-driving system is still being developed, but in the future, the company could make driverless cars available to passengers. the deal comes as the company struggles with its human drivers. uber was fined $8.9 million