The summary of the proposition as it appeared on the general election ballot: Do you want to add a 3% tax on individual Maine taxable income above $200,000 to create a state
fund that would provide direct support for student learning in kindergarten through 12th grade public
education?
Information on the language of the proposition is from the Official Voter Information Guide issued by the Maine Secretary of State: https://www1.maine.gov/sos/cec/elec/upcoming/citizensguide2016.pdf
A total of 3727 votes were cast by citizens abroad; 2844 in favor and 883 against. The state of Maine does not tabulate these votes by county.
Source for Popular Vote data: Maine Secretary of State. 2016 Election Results, Maine Secretary of State (http://www.maine.gov/sos/cec/elec/results/2016/referendum16.xlsx) (accessed 16 Dec 2017)