Note 10 - Profit-sharing Plan

12 Months Ended

Dec. 31, 2019

Notes to Financial Statements

Compensation and Employee Benefit Plans [Text Block]

10.

Profit-Sharing Plan

We offer a

401

(k) profit-sharing plan (the Plan) covering eligible U.S. employees to make tax deferred contributions, a portion of which are matched by us. We

may

make discretionary profit sharing contributions to the Plan in an amount determined by our Board of Directors. Our contributions vest ratably over

six

years of employment and amounted to approximately

$0.4

million,

$0.3

million and

$0.2

million for

2019,

2018

and

2017,

respectively.