NOTE 19. REVENUES BY PRODUCT CATEGORY AND GEOGRAPHIC REGION AND SIGNIFICANT CONCENTRATIONS

Revenue Information

The following is a summary of our revenues by product category and represents our results from continuing operations for the three and six months ended September 30, 2017 and 2016 (in thousands).

	Three Months Ended September 30,				Six Months Ended September 30,
Revenues by Product Category	2017		2016		2017		2016
Instruments (1)	$	9,164	$	9,823	$	17,927	$	19,922
Consumables (2)		46,369		45,512		92,409		90,201
Other products (3)		3,321		3,217		6,776		6,125
Product sales, net	$	58,854	$	58,552	$	117,112	$	116,248

(1)	Instruments include chemistry analyzers, hematology instruments, VSpro specialty analyzers, i‑STAT analyzers and urinalysis instruments.

(2)	Consumables include reagent discs, hematology reagent kits, VSpro specialty cartridges, i‑STAT cartridges, urinalysis tests and rapid tests.

(3)	Other products include products using the Orbos process and extended maintenance agreements.

The following is a summary of our revenues by geographic region based on customer location and represents our results from continuing operations for the three and six months ended September 30, 2017 and 2016 (in thousands).

	Three Months Ended September 30,				Six Months Ended September 30,
Revenues by Geographic Region	2017		2016		2017		2016
North America	$	46,920	$	47,017	$	93,889	$	93,790
Europe		8,338		8,033		16,643		16,391
Asia Pacific and rest of the world		3,596		3,502		6,580		6,067
Total revenues	$	58,854	$	58,552	$	117,112	$	116,248

Significant Concentrations

During the three months ended September 30, 2017, four distributors, MWI Veterinary Supply, Inc., Henry Schein, Inc., Patterson Companies, Inc. and Abbott Point of Care, Inc. accounted for 22%, 14%, 11% and 11%, respectively, of our total worldwide revenues. During the six months ended September 30, 2017, four distributors, MWI Veterinary Supply, Inc., Henry Schein, Inc., Patterson Companies, Inc. and Abbott Point of Care, Inc., accounted for 22%, 15%, 11% and 10%, respectively, of our total worldwide revenues.

During the three months ended September 30, 2016, four distributors, MWI Veterinary Supply, Inc., Henry Schein, Inc., Abbott Point of Care, Inc. and Patterson Companies, Inc. accounted for 20%, 14%, 11% and 10%, respectively, of our total worldwide revenues. During the six months ended September 30, 2016, four distributors, MWI Veterinary Supply, Inc., Henry Schein, Inc., Patterson Companies, Inc. and Abbott Point of Care, Inc., accounted for 20%, 13%, 11% and 10%, respectively, of our total worldwide revenues.

Concentration of credit risk with respect to accounts receivable is primarily limited to certain distributors to whom we make significant sales. Two distributors accounted for 29% and 12%, respectively, of our total receivable balance as of September 30, 2017. Three distributors accounted for 26%, 13% and 10%, respectively, of our total receivable balance as of March 31, 2017.