The mistake you and others make is the assumption that this year's ice is anything like previous years. Or that this year's climate is anything like previous years. Or that atmospheric circulation or ocean currents and temperatures are anything like previous years.
You can crunch numbers all you want, but if circumstances in the past in no way resemble current circumstances, then it's just GIGO.
You can't treat a transforming system as if it's a static one and derive anything useful.
We have variations on this post LITERALLY EVERY YEAR. One year they will be right, much like a stopped clock. When that year comes, don't delude yourself that you deserve credit for your foresight.
To underscore Peter's point, I've made similar assertions, presented similar tables of data, made similar dire observations about the ice, only to have it act inconsistent with my predictions.
In short, in spite of the state of the ice, in spite of previous years behavior, because of the state changes taking place in the system at this level of coverage and volume, those statistical analyses lose their predictive power. What I've seen is an almost "compressive" feedback behavior, where other forces come into play slowing the melt.
My current working hypothesis about this can be summarized thus: once melt retreats past about 75N over all, the system dynanimics change sharply. My thought is, that open water becomes a buffer which more efficiently and evenly redistributes heat. I think the dynamics of phase change come into play as well, with heat which previously melted ice, taken up by evaporation, which in turn further contributes to increased albedo. To summarize, we see increasing feedbacks from different mechanisms that don't exist or are retarded at higher levels of ice coverage. I think they are the only reason we aren't seeing open water at 90N by early August.