Investments at March 31, 2022 primarily consisted of corporate bonds that have maturities of less than 36 months, a certificate of deposit and marketable equity securities. The Company’s corporate bonds consist of both short-term and long-term bonds and are classified as “held-to-maturity” on the Company’s Consolidated Balance Sheets. The Company’s certificate of deposit matures in less than 12 months and is classified as “held-to-maturity” on the Company’s Consolidated Balance Sheet, or classified as cash and cash equivalents if the corporate bonds are purchased 90 days or less from maturity. The Company’s marketable equity securities consist of mutual funds that primarily invest in U.S. government bonds, U.S. government agency bonds, corporate bonds and other asset-backed debt securities. Dividends from these funds are automatically re-invested. The Company may also invest excess cash balances in money market accounts, government-sponsored enterprise securities, and/or commercial paper. These securities are classified as cash and cash equivalents on the Company’s Consolidated Balance Sheet. The Company accounts for its held to maturity investments in accordance with FASB ASC 320, Investments – Debt and Equity Securities and its marketable equity securities in accordance with ASC 321, Investments – Equity Securities. We did not record any impairment charges related to our marketable debt securities during the three and six months ended March 31, 2022.

The following tables summarize the Company’s short-term and long-term investments and marketable securities as of March 31, 2022 and September 30, 2021 by measurement category:

	As of March 31, 2022
	(In thousands)
	Cost Basis		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Classified as Cash Equivalents
Commercial notes (due within ninety days)	$	26,678	$	1	$	(1	)	$	26,678
Classified as Held to Maturity
Commercial notes (due within one year)	$	142,912	$	225	$	(307	)	$	142,830
Commercial notes (due within one through three years)	$	201,590	$	-	$	(5,864	)	$	195,726
Certificate of deposit (due within one year)	$	50,000	$	-	$	-		$	50,000
Classified as Marketable Securities
Marketable securities	$	128,805	$	-	$	(6,230	)	$	122,575
Total	$	549,985	$	226	$	(12,402	)	$	537,809

	As of September 30, 2021
	(In thousands)
	Cost Basis		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Classified as Held to Maturity
Commercial notes (due within one year)	$	56,627	$	803	$	-		$	57,430
Commercial notes (due within one through three years)	$	195,595	$	1,151	$	(103	)	$	196,643
Certificate of deposit (due within one through two years)	$	50,000	$	-	$	-		$	50,000
Classified as Marketable Securities
Marketable securities	$	127,481	$	-	$	(753	)	$	126,728
Total	$	429,703	$	1,954	$	(856	)	$	430,801