4. Cash Equivalents and Marketable Securities

As of December 31, 2021 and 2020, $68.8 million and zero, respectively, of marketable securities had maturities of more than one year and are classified as long-term assets.

There were $176.5 million and $14.7 million of investments in an unrealized loss position of $0.3 million and $3,000 as of December 31, 2021 and 2020, respectively. During the years ended December 31, 2021, 2020 and 2019, the Company did not record any other-than-temporary impairment charges on its available-for-sale securities. Based on the Company’s procedures under the expected credit loss model, including an assessment of unrealized gains on the portfolio after December 31, 2021, the Company concluded that the unrealized losses for its marketable securities were not attributable to credit and therefore an allowance for credit losses for these securities has not been recorded as of December 31, 2021. Also, based on the scheduled maturities of the investments, the Company was more likely than not to hold these investments for a period of time sufficient for a recovery of the Company’s cost basis.

The Company recognized no material gains or losses on its cash equivalents and current and non-current marketable securities as of December 31, 2021 and as a result, the Company did not reclassify any amounts out of accumulated other comprehensive income for the year then ended.