S&P 500 · April 21, 2020

The day after oil went below zero

-3.07%

single-day change vs previous close

Part of a longer stretch

The COVID rebound

early in it · 2020-03-23 → 2020-08-18, +51.51% over the whole period

What happened that day?

21 April 2020 — the S&P 500 fell 3.07%
The day before, the May contract for US crude had printed a negative price for the first time ever. With nowhere left to store the barrels, a seller had to pay someone to take them
On this session the June contract slid too. That turned a one-day accident into a statement about demand itself
Energy companies and the banks that had lent to them led the fall, and the rest of the index followed
When lockdowns stop people moving, oil accumulates. Stored oil costs money, and once the tanks are full the price goes below zero
The low of this episode was already a month behind, on 23 March. The index bounced the very next session
From the 19 February high to the 23 March low the index fell 33.92%

Sources

Every figure on this page is recomputed from the original daily closing prices and checked against them at build time. The account of what happened is put together from the public record; where a specific source was consulted it is listed above.