However, this efficiency comes with a trade-off. The investor has traded the absolute safety of government-insured banking for the relative safety of market liquidity. The equation favors the investor in times of high interest rates and stability, but it exposes them to the minute fluctuations of the debt market.
However, the rise of discount brokerages like Charles Schwab created a new beast: the uninvested cash balance. When a client sells a stock, they have cash sitting idle. Idle cash is mathematically inefficient—it has a velocity of zero. To solve this, brokerages invented the "sweep" program. Instead of cash sitting in a static ledger entry, it is automatically "swept" into a money market mutual fund. This is where SPAX enters the equation. spax math