Despite predictions of an impending nurse shortage, the current number of working registered nurses has surpassed expectations in part due to the number of baby-boomer RNs delaying retirement, a study by the RAND Corp. found. The study, published online Wednesday by Health Affairs, notes that the RN workforce, rather than peaking in 2012 at 2.2 million – as the researchers predicted a decade ago – reached 2.7 million that year and has continued growing. The trend of nurses delaying retirement accounted for an extra 136,000 RNs in 2012, the study suggests. Shifts in retirement benefits and "economic uncertainty in general" could have contributed to their decisions to extend their careers, said David Auerbach, the study's primary author and a policy researcher at RAND.