Using http://www.socialsecurity.gov/OACT/q...arly_late.html I
get this result:

Someone born Jan 2, 1946 starts benefits, receives percentage as
follows:

Jan 2012 = 100% Age 66
Jan 2013 = 108% Age 67
Jan 2014 = 116% Age 68
Jan 2015 = 124% Age 69
Jan 2016 = 132% Age 70
Feb 2016 = 132% Still age 70

The calculator says "You choose to receive benefits 50 months after
you reach your normal retirement age. However, because delayed
retirement credits do not apply after age 70, your benefit will be
increased only for 48 months of delayed retirement. Your benefit will
be 132 percent of your primary insurance amount.".

You are possibly confusing the *benefit* associated with delayed
retirement with the *penalty* associated with early retirement.

- quote -

"In the case of early retirement, a benefit is reduced 5/9 of one
percent for each month before NRA, up to 36 months. If the number of
months exceeds 36, then the benefit is further reduced 5/12 of one
percent per month."

See http://www.ssa.gov/OACT/ProgData/ar_drc.html

Although baby boomers are supposed to get 8% credit for each year up
to age 70, the last year is is only 100 * 8 / 124 = 6.45%.

--
Ron