Amid new signs of belt-tightening at Microsoft, our analysis of hiring patterns suggests that Google was actively bracing for the possibility of economic turmoil months before the Redmond software company started to rein in its own growth.

Was Microsoft being strategically opportunistic, gobbling up good people as the job market turned south? Or was the search giant being more nimble and responsive to signs of trouble in the broader economy?

Whatever the case, our number-crunching shows that Google noticeably slowed its pace of hiring in the quarter ended June 30 this year, adding a net total of less than 500 permanent employees in that period -- significantly fewer than it had been adding in previous quarters. (See chart above.)

At the same moment, Microsoft was ramping up its hiring, adding a net total of nearly 4,300 employees in the June quarter. Microsoft had added a mere 1,416 employees in the same quarter the previous year, according to data from the company. The hiring boom continued into the September quarter of this year, with Microsoft adding more than 3,000 employees in that period.

Since then, Microsoft has slowed things down considerably, adding just 380 employees in November, according to the latest numbers provided by company spokesman Lou Gellos this afternoon. The phrase "hiring freeze" isn't entirely accurate, because the company is continuing to make strategic hires, including its poaching of Yahoo search technology executive Sean Suchter.

But it's clear that Microsoft has put a chill on hiring for now.

Microsoft CEO Steve Ballmer told shareholders last month to expect "much, much slower growth" in employee headcount for the remainder of this fiscal year (which ends June 30) and probably into next fiscal year, due to the economy. Chris Liddell, Microsoft's chief financial officer, had outlined plans in October to reduce operating expenses by as much as $500 million this fiscal year.

In a report to clients yesterday, Morgan Stanley analyst Adam Holt cited a hiring slowdown as one of "several levers" the company could pull to minimize the impact of the economic slowdown on earnings. (Also see this Seattle P-I post on the report.)

"We believe that the company has already effectively stopped hiring, which suggests expense growth will be in the 6-8% range this year vs. the 11% in guidance," Holt wrote in the report, which followed a meeting between Morgan Stanley analysts, Liddell and other Microsoft executives.

In addition to slowing its pace of hiring, Google has scaled back its plans for its new Kirkland campus. And the search company last month acknowledged plans to cut back on its workers employed under temporary contracts.

Microsoft also relies heavily on contract workers -- "orange badges," as they're known on the Redmond campus.

After some digging around this week, I haven't found any evidence that Microsoft has a centralized plan for big reductions in its contract work force. But it's possible that individual groups and divisions could consider contractor cutbacks as one means of reducing costs.

And Microsoft could try to make such cutbacks under the radar, because contractors aren't included in the employment figures it reports publicly.

Significant layoffs in the permanent workforce would be a shocker at Microsoft, which has grown every year since its inception. Then again, in these times of unprecedented economic turmoil, maybe there's no such thing as a shocker anymore.

"We do not anticipate Microsoft to announce any headcount reduction measures near-term," Morgan Stanley's Holt wrote in his report. "However, should the economy deteriorate further, we could see Microsoft announce a headcount reduction although not likely before next spring."