The adjusted estimate is a result of the law's Medicaid expansion and the subsidies for private insurance plans proving less costly than initially anticipated. According to the Times, economists say that the law has also benefitted from a weak economy over the last half-decade, during which time health spending has slowed dramatically.
It still remains unclear if Obamacare's cost-control mechanisms will work effectively when the economy improves and health spending rises once again.
Roughly 100,000 people signed up for insurance last month using the troubled online federal health exchange HealthCare.gov.
This post has been updated.