According to publicly filed financial statements, 40 U.S. oil producers collectively wrote down $48 billion worth of assets in the first quarter of 2020, the largest quarterly adjustment since at least 2015. Low crude oil prices contributed to significant declines in revenue and the value of these companies’ proved reserves. Write-downs reflect negative adjustments in asset values, for example, when a producer acknowledges the value of an oil property has declined to less than the cost of developing it and the company updates its estimate of the oil’s value.