It's the percentage of value the NJ pension funds lost through February 2016.
NJ's pension funds are actuarially assumed to return 7.9% annually. This 7.9% is what Moody's used when it estimated that NJ's pension funds would start zeroing-out in 2021. If NJ doesn't meet the 7.9% return then the funds start zeroing-out even sooner and state aid is gutted even sooner.
This comes a few days after Standard & Poor's lowered its outlook for NJ from stable to negative.