Last year on this date the total ice cover was just 67%, when GDP was going negative supposedly because of the terrible winter we were having. The year before, ice cover on this date was 74.3%. As of yesterday, ice covers 84.4% of the Great Lakes, 25% ahead of last year.
Will GDP tank in 1Q2015 because of this?
We won't have what passes for complete knowledge about this until the end of June.
Data here.
