At the heart of today's highly anticipated recall election in Wisconsin is a battle over the collective bargaining rights of public sector unions. But as often happens with statewide elections, the race has expanded to become a referendum on Wisconsin's economy under Gov. Scott Walker.

"Wisconsin gained jobs in 2012, we gained jobs in 2011," Walker said during a debate with his opponent, Milwaukee Mayor Tom Barrett, last Thursday.

According to the Bureau of Labor Statistics, the number of employed workers in December 2011  was higher than the number of employed workers in January  2011. In January, Wisconsin had  an employed work force of 2,833,068, while in December it had reached 2,843,199 - an increase of 10,131 - so it is accurate to claim that the state ended the year with a larger employed work  force than when the year began.

But  there were several months in which the number of employed Wisconsin residents decreased.  According to the Bureau of Labor Statistics, a total of 21,000 jobs were lost in Wisconsin in 2011. To compare, the BLS calculates that the U.S. gained roughly 1.8 million jobs in 2011.

In 2012, the state employment numbers have shown a positive trend, with slight increases each month.  Wisconsin's unemployment rate is  6.7 percent, lower than the national average of 8.2 percent, and a percentage point below from when Walker took office in January 2011.

In 2011, the average  income in Wisconsin was $40,073, according to the nonpartisan Wisconsin Budget Project, slightly lower than the national average of $41,663. Wisconsin's average personal income rose higher in 2011  than the national average - 4.8 percent  compared with 4.3 percent.

One of the hallmarks of Walker's governorship that he often touts has been a reduction in  the state's $3.6 billion budget deficit.

According to figures from the Wisconsin Department of Administration, Wisconsin will have a positive budget balance of $154.5 million or, in other terms, a surplus of $89.5 million, by June 30, 2013. (Roughly $65 million of the $154.5 million is a modest reserve for the state, so it can't be spent by an administration.)

On his campaign website, Walker claims to have  erased this deficit "without raising taxes" while giving school districts and local governments "the tools to balance their budgets without the massive layoffs seen in other states."

While this claim is true,  opponents would note that it ignores the pay decreases faced by union workers as a result of the law Walker signed.

Under this law, called Wisconsin Act 10, state and local government workers are required to increase contributions to their health insurance and pensions. As a result, many union workers, such as teachers, have faced pay cuts.

In the Nicolet Union High School District, for example, the average teacher salary decreased by slightly more than $2,000 - from $74,431 to $72,125 -  between the 2010-2011 school year and the 2011-2012 school year, according to reports from the Wisconsin Department of Public Instruction.

In the Abbotsford School District, where the average teacher salary was notably lower, teachers still saw their salaries decline  between school years. In Abbotsford, the average teacher salary dropped by almost $400 between the 2010-2011 school year and the 2011-2012 school year, going  from $48,805 to $48,415.