The tables underneath represent the ratio of five major North American Lakes in ice over seperated 2 decades era.
Overall, all five lakes experienced the decline of ice covered percentages in 1993 to 2012, although the decreased amount varied. Lake Superior in the other hand encountered the greated drop, while lake Ontario faced the tiniest fell amongst all the five lakes.
The highest percentages belongs to the lake Erie, which was around 30 percents. The gap between the greatest and the lowest,Erie lake and Ontario lake, was incredibly massive. The least percentages recorded was owned by Ontario, with only 5 percents of ice covered.
However, there are 2 lakes that have similar ice coverage ratio,which are Superior lake and Huron lake. Although the number of percentages are quite the same in the first period,the ice layer of Superior lake in the second time period plummeted more dramatically compare to Huron lake.