Dear IANA team,

For personal reasons, I've been trying to find out about DST on Madeira Island, Portugal during the past century. Long story short. I've researched a lot and along the way I've been told that even IANA is actually missing some records for when Madeira Island was congruent in its time changes with mainland Portugal (Lisbon) and when it did its own thing. 

I've eventually found the original law text for Madeira Island from 1982 and am hereby submitting it to you. You don't have any mistake in your tzdb, but seemingly part of it is based on the assumption that Madeira did not apply DST under certain years, and you didn't have prove of it. Here comes the prove. :) 

With best regards,
Stefanie Schlosser