Impact of increasing retirement age on the size of the economy

From the CBO blog:

Raising any of the ages of eligibility would cause some people to work longer, thereby increasing the size of the workforce and the economy. Although the magnitude of those effects is difficult to predict, CBO estimates that:

Raising Social Security’s early eligibility age to 64 or the full retirement age to 70 would, in the long term, boost the size of the workforce and the economy by slightly more than 1 percent.
Raising Medicare’s eligibility age to 67 would also boost the size of the workforce and the economy, but by a much smaller amount.