No doubt you’ve made some tough belt-tightening decisions in the past few months, and they’ve put extra pressure on your employees. Those moves have taken a toll on worker loyalty, commitment and motivation, according to new research. Who’s complaining the most?

A recent survey found that “engagement levels” — consultant-speak for employee loyalty and motivation — have dropped 9% across all classes of workers. But there’s more: That loyalty and motivation level has dropped almost 25% for top performers over the past year.

The stars are unhappy

Indeed, top performers appear to be the least-happy campers. Nearly 20% fewer of the best and brightest would recommend others take jobs with their employers. Twenty-six percent are less satisfied with advancement opportunities than they were last year, and they’re 14% less likely to stick with their current employer once the economic picture brightens.

Two more disturbing stats from the top-performers: 29% say they’re less confident this year that management will be able to grow the business. And 41% think pay and benefit changes instituted over the past 12 months have hurt work quality and customer service.

Overall, not a pretty picture. What can employers do? There’s probably no secret formula. Open communication, performance-based incentives and low-cost perks — flexible schedules, for instance — can certainly help.

And it also pays to remember that employees are a notoriously fickle lot. As the economy improves and everybody gets a few more bucks in their pockets, attitudes will likely improve.

For a look at the Executive Summary of the Watson Wyatt survey, go here.