Note

Revenue; Accounts and Unbilled Receivables

Staffing services include the augmentation of customers' workforce with our contingent employees performing services under the customer's supervision, which provides our customers with a source of flexible labor at a competitive cost. Customer contracts are typically annual contracts but

may

be terminated upon

days' notice for any reason.

The Company recognizes revenue when control of the promised services is transferred to customers and for the amount that reflects the consideration we are entitled to receive in exchange for those services. Furthermore, revenue is recognized over time based on a fixed amount for each hour of staffing service provided as our customers benefit from our services and as we provide them.

Performance Obligations —

A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. A contract's transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. The Company's customer contracts have a single performance obligation to transfer the individual goods or services, and it is

not

separately identifiable from other promises in the contracts and is, therefore,

not

distinct. Performance obligations are satisfied at the point in time the HCS employees work on behalf of the customer. Contract costs include compensation, benefits and overhead when appropriate. Because of the nature of the contracts and the fact that revenue is earned at the time the employee works for the customer,

contract estimates are necessary.

Contract Balances —

The timing of revenue recognition, billings and cash collections results in accounts receivable and unbilled receivables (the "contract assets"). The Company bills customers generally every other week based on the work performed during the

two

-week period ended the week prior to billing. Generally, billing occurs after revenue recognition, resulting in contract assets. The Company does

not

receive advances or deposits from its customers.

Disaggregation of Revenue —

All revenue is generated from customers that provide healthcare services in Georgia. The following is a disaggregation of the Company's revenue, unaudited, in thousands, into categories that best depict how the nature, amount, timing, and uncertainty of revenues and cash flows are affected by economic factors.

	Three Months Ended March 31, 2021 (unaudited)				Three Months Ended March 31, 2020 (unaudited)
Type of Customer
CSB	$	11,739	94.8	%	$	13,767	98.1	%
Other		641	5.2	%		266	1.9	%
Total	$	12,380	100.0	%	$	14,033	100.0	%

Accounts and unbilled receivables are summarized as follows, in thousands:

	March 31, 2021 (unaudited)			December 31, 2020
Accounts receivable	$	2,928		$	2,705
Unbilled receivables (Contract Assets)		2,119			2,303
Allowance for doubtful accounts		(1	)		—
Total	$	5,046		$	5,008

During the

three

months ended

March 31, 2021

66%

of service fee income was generated from

three

customers. For the

three

months ended

March 31, 2020

59%

of service fee income was generated from

three

customers. As of

March 31, 2021

and

March 31, 2020

59%

and

67%

of accounts and unbilled receivables were due from

three

and

four

customers, respectively. At

March 31, 2021

and

March 31, 2020

89%

and

97%

of accounts and unbilled receivables were due from

CSB customers, respectively.