As filed with the Securities and Exchange Commission on March 22, 2019 UNITED STATES SECURITIES EXCHANGE COMMISSION WASHINGTON, D.C. 20549 Form 20-F ☐ REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934 or ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED DECEMBER 31, 2018 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 or ☐ SHELL COMPANY REPORT PURSUANT TO ...