Couldn't resist posting this chart of T-bill yields, which are now trading at effectively a ZERO rate of interest. In exchange for putting your money into the safest investment on the planet, you now receive NOTHING in return. This is a measure of how high the level of panic, and how strong the demand for safety is. As I recall, there was a time during the Great Depression when short-term government securities actually paid a negative rate of interest, but I can't locate the data to be sure.
If T-bill yields start rising above zero, that will be an excellent sign that sentiment is improving.