3 percent is insane and not sustainable. One year treasuries are at 2.7 percent. I could short treasuries and put all my money in Robinhood... ripe for arbing.

3 percent is insane and not sustainable. One year treasuries are at 2.7 percent. I could short treasuries and put all my money in Robinhood... ripe for arbing. How are they making money? My first inclination is to think parking my money with them is super risky... Edit: Looking at today's market and interest rates.