UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

________________________

SCHEDULE 14A

(RULE 14a-101)

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.    )

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National Instruments Corporation

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 Supplemental CEO Compensation Information 

   National Instruments CEO Compensation    One-time Initial Grant for new CEOWas 62% of total comp in 2017  One-time Initial Grant does not repeat  *From NI proxy statements  New CEO Equity Compensation 

   NI Executive Compensation Philosophy  Total compensation opportunities should be competitiveTotal compensation should be related to NI’s performanceTotal compensation should be related to individual performanceEquity rewards help executives think like stockholdersNI’s overall amount of equity awards should be related to its revenue growthThe same compensation programs should generally apply to both executives and non-executive employees whenever possible  2017 New CEO Total CompensationHighly variable 

   $1.29BILLION REVENUEIN 2017  Continuous INVESTMENT IN R&D  35,000+ CUSTOMERS WORLDWIDE  Long-Term Track Record of Growth  Revenue in millions USD  NI at a Glance   Founded in 1976Global Operations in more than 50 countries Approximately 7,300 employeesBroad customer base, more than 35,000 companies served annually Diversity with no industry >15% of revenue 

   Increasing Shareholder Value with Consistent Profitability 

 GAAP to non-GAAP Operating Income Reconciliation