Since Jim Hunt’s final term as governor, North Carolina policymakers and education activists have been fixated on raising the salaries of K-12 public school teachers to a “national average” compiled by the nation’s largest teachers union, the National Education Association.

Hunt even highlighted his advocacy for raising teacher pay in an op-ed column published in the Jan. 5 edition of Raleigh’s News & Observer.

“In the next four years, let’s raise the pay of our public school teachers to the national average. Not talk about it, or vaguely promise it, but do it,” Hunt wrote. The former governor also noted increasing public teachers’ pay in North Carolina, will bump up the national average as well, and the General Assembly will have to continue boosting salaries to chase that higher figure.

But what’s so special about the national average, and why is it such a rallying point for public educators when no other major industry group in North Carolina seems obsessed with it?

Data from the NEA conclude that North Carolina’s average teacher salary ranks 46th nationally — prodding business leaders, politicians, liberal rabble rousers, and journalists to try to shame taxpayers into coughing up more money, acting as if current pay scales insult public school teachers. They say reaching the national average will prevent an impending exodus of our best educators to other states or other lines of work.

There’s no evidence of flight from the classroom. The state Department of Public Instruction’s 2012-13 “teacher turnover report”(PDF) found that a mere 0.9 percent of the state’s 96,000 teachers — 887 — said they left their positions because they were dissatisfied with teaching or making a career change. About half that many more said they left to take a job in another state.

Teachers themselves are giving little indication that inadequate pay is likely to cause a revolt, as 14.3 percent of them changed jobs last year. (The top three reasons teachers in North Carolina move on, by far — accounting for 46 percent of turnover in the most recent report — are taking a job in another North Carolina school district, retiring, or moving to a non-teaching position in the same school district.) More teachers left their jobs because their family moved (1,346) than those who resigned to take a job in another state (455) or were “dissatisfied with teaching or making a career change” (887).

Public school teachers may be paid less than their counterparts in other states, but many private sector employees are, too.

Recently, Carolina Journal‘s Don Carrington used federal employment statistics and found that North Carolina private-sector wages in 2012 were, on average, 87.5 percent of their private-sector peers nationally; local public educators (the industry group including all public K-12 teachers, staff, and administrators) received 85.1 percent of the salaries of their peers across the country.

Is this a reasonable benchmark or goal? Looking at other states, Carrington — who was the state’s deputy director of labor market information during the Martin and Hunt administrations — found that educator pay in 17 states was within 5 percentage points of that state’s private-sector benchmark. Public-sector compensation should have some relationship to private-sector pay, rather than some arbitrary national average.

Consider this: If the 2014 session of the General Assembly offered a 3-percent raise to K-12 teachers, North Carolina’s public school educators should be in line with the state’s private sector standard. A raise of that magnitude would cost a few hundred million dollars. Reaching the NEA’s national average, by contrast, would cost more than a billion dollars — and would not guarantee better classroom results.

To be sure, there’s plenty of room for disagreement about the best ways to allocate teacher pay. Effective new teachers shouldn’t have to wait five or six years to get their first raise. Performance-based pay could reward the teachers who are bringing out the best in their young charges. And if certain school districts have chronic problems keeping their best teachers, local officials could boost local supplements.

For now, though, those pushing North Carolina to raise teacher pay to the national average need to provide a better justification, based on evidence rather than guilt or shame.

Rick Henderson is managing editor of Carolina Journal.