NOTE 8.UNEARNED REVENUE

The Company records unearned revenue when we have either received payment or contractually have the right to bill for services in advance of the services or performance obligations being performed. Deferred revenue recognized in the three months ended September 30, 2021 and 2020 were $47.3 million and $43.4 million, respectively. Deferred revenue recognized for the nine months ended September 30, 2021 and 2020 were $139.6 million and $129.4 million respectively. Changes in unearned revenue were as follows:

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As of September 30, 2021 and December 31, 2020, the Company had long-term unearned revenue of $23.1 million and $18.0 million, respectively, recorded in other long-term accrued liabilities. Unearned short-term revenue is recognized over the next 12-month period. The majority of unearned long-term revenue is recognized over a period of five years or less with immaterial amounts recognized through 2032.