The Company invests a portion of its excess cash balances in short-term debt securities and may, from time to time, also invest in long-term debt securities. Investments at December 31, 2018 consisted of corporate bonds with maturities remaining of less than 36 months. The Company may also invest excess cash balances in certificates of deposits, money market accounts, government-sponsored enterprise securities, corporate bonds and/or commercial paper. The Company accounts for its investments in accordance with FASB ASC 320, Investments – Debt and Equity Securities. At December 31, 2018, all investments were classified as held-to-maturity securities.

The following tables summarize the Company’s short-term and long-term investments as of December 31, 2018, and September 30, 2018.

	As of December 31, 2018
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Commercial notes (due within one year)	$	53,980,307	$	201,216	$	(799,900	)	$	53,381,623
Commercial notes (due within two years)	$	59,595,287	$	27,609	$	(201,793	)	$	59,421,103
Total	$	113,575,594	$	228,825	$	(1,001,693	)	$	112,802,726

	As of September 30, 2018
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Commercial notes (due within one year)	$	46,400,176	$	—	$	(429,050	)	$	45,971,126
Commercial notes (due within two years)	$	—	$	—	$	—		$	—
Total	$	46,400,176	$	—	$	(429,050	)	$	45,971,126