As is his wont, Needham’s Charlie Wolf waited until the middle of Apple’s (AAPL) current quarter to issue his analysis of the last. As usual, it was worth the wait.

In a note to clients Friday entitled “What a Streak,” he uses a series of charts based on IDC data to zero in on where and by how much Mac sales growth outpaced the Microsoft (MSFT) Windows PC market in the March quarter — the 20th quarter in row it has done so.

Overall, Mac shipments grew 27.7% year over year in Q1 2011 (Apple’s fiscal Q2) against a backdrop of a 1.2% decline in total PC shipments — a decline than would be even sharper if the number didn’t include Macs. But as Wolf points out, there were pockets of extraordinary growth. Among the highlights:

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  They’re everywhere: Mac sales grew faster than PC sales in every regional market, but the contrast was especially striking in Asia, where Mac shipments were up 69.4% (vs. 8.8%) and in Japan, where they grew 21.1% (vs. -16.1%).

• Business is booming: Shipments to business were up 66% (vs. 4.5%) in March, a pace Wolf describes as “torrid.” He used the same adjective to describe business sales in the December quarter, when they were up 65.4% (vs. 9.7%). “What we initially viewed as a one-quarter blip in the business market,” he writes, “appears to be emerging as a durable pattern.”
• Government is growing: Shipments to government grew 155.6% (vs. 2.3%), down from 550% (vs. 8.4%) in December. In both cases Mac sales grew from a small base, but by March Apple’s government business had grown to represent nearly 3% of Mac unit sales.
• Apple is raking in the cash: Because Mac prices have held steady while PC prices were deteriorating, Apple’s dollar share of the market is growing faster than its unit share. For example, the Mac commands less than 9% of the European home market by unit shipments, but 17.9% by dollar. See chart below: