Inventories

9 Months Ended

Sep. 30, 2021

Major classes of inventories are presented below. Readily Marketable Inventories ("RMI") are agricultural commodity inventories such as corn, soybeans, wheat, and ethanol co-products, among others, carried at net realizable value which approximates fair value based on their commodity characteristics, widely available markets, and pricing mechanisms. The net realizable value of RMI is calculated as the fair value (spot price of the commodity in an exchange), less cost of disposal and transportation based on the local market. All other inventories are held at lower of cost or net realizable value.


(in thousands)	September 30, 2021		December 31, 2020		September 30, 2020
Grain and other agricultural products (a)	$	732,512	$	1,025,809	$	557,808
Frac sand and propane (a)	18,481		12,477		10,064
Ethanol and co-products (a)	105,052		114,895		59,543
Plant nutrients and cob products	161,759		139,885		120,173
Total Inventories	$	1,017,804	$	1,293,066	$	747,588

(a) Includes RMI of $700.3 million, $983.2 million and $523.3 million at September 30, 2021, December 31, 2020 and September 30, 2020, respectively.

Inventories do not include 2.0 million, 3.0 million and 2.3 million bushels of grain held in storage for others as of September 30, 2021, December 31, 2020 and September 30, 2020, respectively. The Company does not have title to the grain and is only liable for any deficiencies in grade or shortage of quantity that may arise during the storage period. Management has not experienced historical losses on any deficiencies and does not anticipate material losses in the future.

Lower of cost or net realizable value charges were $3.4 million and $10.9 million for the nine months ended September 30, 2021 and September 30, 2020, respectively. The current year charge primarily relates to certain fertilizer values decreasing after the spring application season. The charge in the prior year was a result of lower ethanol market prices and decreased demand as a result of the COVID-19 pandemic