If you’re floating a mortgage rate, or have yet to lock one in, today may be a good day to call your loan officer. Friday morning, the government releases its Non-Farm Payrolls report at 8:30 AM ET.

The Non-Farm Payrolls report is more commonly called the “jobs report” and, lately, it’s been Wall Street’s domestic economic metric of choice. As jobs go, so go markets.

In the 12 months beginning November 2007, the economy shed 2.3 million on its way to losing more than 7 million jobs by the end of 2009.

It’s no coincidence that the stock market has been wayward. Jobs are a keystone in the U.S. economy and the connection between jobs and growth is straight-forward :

1. Workers spend more than non-workers and consumer spending is the economy’s largest single component
2. Workers pay more taxes to governments and, when governments have money, they build and spend on projects
3. Additional consumer and government spending creates revenue for businesses which, in turn, hire more workers.

It’s a self-reinforcing cycle. More employees begets more employees.

As a rate shopper , this is an important understanding. Job loss was, in part, behind the big drop in mortgage rates since 2007. A weak economy drives investors away from equities and into safer securities such as mortgage bonds (which are backed by the U.S. government).

The excess demand causes mortgage rates to drop and that’s exactly what we’ve seen. Since late-2007, mortgage rates have been in decline.

In the first 11 months of 2011, though, 1.5 million people went back to work; the economy showed signs of shoring up and economic optimism is returning. Mortgage markets have temporarily ceded to the Eurozone, but with one more strong jobs report to close out the year, momentum could tip and stock markets could roll.

If that happens, mortgage rates will rise. Maybe by a lot.

This is why Friday’s Non-Farm Payrolls data is so important. Economists expect that 150,000 new jobs were created in December. If the government’s actual number is larger than that, prepare for higher mortgage rates.

Conversely, if job creation falls short of 150,000, mortgage rates may fall.

If the prospect of rising mortgage rates makes you nervous, remove your nerves from the equation. Call your loan officer and lock your rate ahead of Friday’s Non-Farm Payrolls release.