NOTE 8. REVENUE

As of September 30, 2019, we had a total of $7.8 million of deferred service revenue from our service contracts, $6.4 million of which was recorded as “Deferred service revenue, current” to be recognized over the next year and the remaining $1.4 million was recorded as “Deferred service revenue, non-current” to be recognized in the next 2 to 4 years. Revenue recorded in the three and nine months ended September 30, 2019 includes $1.3 million and $5.7 million, respectively, of previously deferred revenue that was included in “Deferred service revenue, current” as of December 31, 2018. Contract assets as of September 30, 2019 and December 31, 2018 were not material.

As of September 30, 2019, we had a total of $0.4 million of deferred commissions included in “Prepaid expenses and other current assets” which is recognized as the related revenue is recognized. Additionally, as a practical expedient, we expense costs to obtain a contract as incurred if the amortization period would have been a year or less.

A summary of our revenue by geographic location for the three and nine months ended September 30, 2019 and 2018 is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2019		2018		2019		2018
North America	$	10,393	$	8,960	$	33,165	$	25,974
Europe (including the Middle East and Africa)		4,940		2,914		11,423		10,614
Asia Pacific		6,582		6,286		18,373		22,512
Total	$	21,915	$	18,160	$	62,961	$	59,100

A summary of our revenue by category for the three and nine months ended September 30, 2019 and 2018 is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
(in thousands)	2019		2018		2019		2018
Instrument revenue	$	11,583	$	6,296	$	29,870	$	21,965
Consumable revenue		6,901		8,854		23,321		27,952
Product revenue		18,484		15,150		53,191		49,917
Service and other revenue		3,431		3,010		9,770		9,183
Total revenue	$	21,915	$	18,160	$	62,961	$	59,100