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 nine months ended December 31, 2017 and 2016 (in thousands).

	Three Months Ended December 31,				Nine Months Ended December 31,
Revenues by Product Category	2017		2016		2017		2016
Instruments (1)	$	10,468	$	9,349	$	28,395	$	29,271
Consumables (2)		45,475		40,353		137,884		130,554
Other products (3)		3,727		3,070		10,503		9,195
Product sales, net	$	59,670	$	52,772	$	176,782	$	169,020

(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 nine months ended December 31, 2017 and 2016 (in thousands).

	Three Months Ended December 31,				Nine Months Ended December 31,
Revenues by Geographic Region	2017		2016		2017		2016
North America	$	46,442	$	41,538	$	140,331	$	135,328
Europe		9,589		7,999		26,232		24,390
Asia Pacific and rest of the world		3,639		3,235		10,219		9,302
Total revenues	$	59,670	$	52,772	$	176,782	$	169,020

Significant Concentrations

During the three months ended December 31, 2017, four distributors, MWI Veterinary Supply, Inc., Henry Schein, Inc., Abbott Point of Care, Inc. and Patterson Companies, Inc. accounted for 21%, 16%, 11% and 10%, respectively, of our total worldwide revenues. During the nine months ended December 31, 2017, four distributors, MWI Veterinary Supply, Inc., Henry Schein, Inc., Abbott Point of Care, Inc. and Patterson Companies, Inc., accounted for 22%, 15%, 11% and 10%, respectively, of our total worldwide revenues.

During the three months ended December 31, 2016, four distributors, MWI Veterinary Supply, Inc., Henry Schein, Inc., Abbott Point of Care, Inc. and Patterson Companies, Inc. accounted for 21%, 14%, 10% and 10%, respectively, of our total worldwide revenues. During the nine months ended December 31, 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.

Concentration of credit risk with respect to accounts receivable is primarily limited to certain distributors to whom we make significant sales. Three distributors accounted for 25%, 16% and 10%, respectively, of our total receivable balance as of December 31, 2017. Three distributors accounted for 26%, 13% and 10%, respectively, of our total receivable balance as of March 31, 2017.