[kbob]

Could that graph possibly be more misleading? Plotting the ratio of a number to one much smaller exaggerates small changes so you miss the big picture: PC sales dwarf Mac sales.

A better graph: two lines, one showing PC sales each year and the other showing Mac sales. It would show that Mac sales are less, and it would also show how much the market has grown since 1984. Even better: the number of machines of each type currently in use.

[pohl]

It depends on what you want to visualize. This graph is great for visualizing the effect of Mac sales outgrowing the pc market for 24 consecutive quarters.

[calciphus]

This graph could just as easily be explained as people with high incomes (Mac users generally do) are more insulated from economic downturn than the people buying $300 laptops. Reading it how you want doesn't make it true.

Even according to the graph, 15x means that one in 16 machines sold is a Mac. Math tells us that's 6.25% market share. That number hasn't appreciably changed in real terms in the last decade. Yes, moving from 4% to 6% is a 50% "growth", if you want to define growth that way. Normally, that's 2% growth.

However, the inability of Mac to grab any significant market share from the overall PC market should be a concern, considering the relative popularity of their other devices.

[pohl]

This graph could just as easily be explained as people with high incomes (Mac users generally do) are more insulated from economic downturn than the people buying $300 laptops.

Not if you look at the labels on the horizontal axis and you know when the downturn actually began.