It's a good time to be in the Navy, career-wise.

The Navy is unique among the services as it expects to grow, not shrink, in the next few years. Officials also project retention to start falling from historic highs as the economy gathers steam — and that's good news for those remaining in uniform.

In fall 2014, the overall chance to advance up the petty officer ranks rose 4.2 percentage points to 27.6 percent, up from 23.4 percent during the spring cycle.

While the advancement shot is a touch lower than 2013, the future is bright. The Navy's top personnel officer says opportunity could stay on a slight upward trend this coming year.

"If retention gets really tough, it's only going to get better for advancement," said Vice Adm. Bill Moran, the chief of naval personnel. "So we're in that sweet spot right now."

In that sweet spot, he said, opportunity could rise again in the spring and possibly the fall this year, so sailors should study hard and hit these next two cycles as hard as they can.

Moran's other focus: eliminating the wild swings that happened during and after the last drawdown.

"My job is to keep us hovering around that line, not get too wildly up or two wildly down, and bring predictability for our sailors," he said.