FORTUNE — Asymco‘s Horace Dediu put this chart together Wednesday after Dell’s DELL earnings miss — the first in which management acknowledged the competition from Apple AAPL and Google GOOG . Dediu writes:

“And so, two years later, the impact of the iPad is becoming abundantly clear, even to the incumbents. The resistance and denial was profound. Even on this blog, the agitation and anxiety when the subject of the iPad as disruptor came up was palpable. Perhaps that is the greatest testament to the disruptive potential of a product.”

See the rest of his post here.