G. Economic Dependency

We had substantial net sales to certain customers during the periods shown in the following table. The loss of any of these customers, or a significant decline in (i) sales to these customers, (ii) the growth rate of sales to these customers, or (iii) these customers' ability to make payments when due, each individually could have a material adverse impact on our net sales and net income. Net sales to any

one

customer representing

10%

or more of the respective period's consolidated net sales were as follows (in thousands):

	Three Months Ended March 31,				Nine Months Ended March 31,
	2021		2020		2021		2020

Customer 1	$	23,215	$	9,271	$	72,001	$	36,047
Customer 2		5,811	(a)		(a)		(a)
Customer 3	(a)			7,599		16,288		17,108
	$	29,026	$	16,870	$	88,289	$	53,155

(a)

Sales were less than

10%

of the respective period's total net sales.

We buy certain products, including beta-alanine, from a limited number of raw material suppliers who meet our quality standards. The loss of any of these suppliers could have a material adverse impact on our net sales and net income. Raw material purchases from any

one

supplier representing

10%

or more of the respective period's total raw material purchases were as follows (dollars in thousands):

	Three Months Ended March 31,				Nine Months Ended March 31,
	2021		2020		2021		2020

Supplier 1	$	5,978		1,930	$	15,765	(a)
	$	5,978		1,930	$	15,765		—

(a)

Purchases were less than

10%

of the respective period's total raw material purchases.

Financial instruments that subject us to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. We place our cash and cash equivalents with highly rated financial institutions. Credit risk with respect to receivables is concentrated with

two

of our largest customers, whose receivable balances collectively represented

52.1%

of gross accounts receivable at

March 31, 2021

and

65.7%

June

30,

2020.

As of

March 31, 2021

we had a receivable balance of

$3.2

million and as of

June 30, 2020

we had a receivable balance of

$3.3

million from a former contract manufacturing customer that we have recorded a bad debt reserve equal to

100%

of the outstanding balance and thus did

not

reflect it in the percentages listed above. Additionally, amounts due related to our beta-alanine raw material sales were

7.4%

of gross accounts receivable at

March 31, 2021,

and

2.5%

of gross accounts receivable at

June 30, 2020.

Concentrations of credit risk related to the remaining accounts receivable balances are limited due to the number of customers comprising our remaining customer base.