Note: my original calculation below rounded the increase to the nearest 0.0% as indicated on the SS webpage. However, Social Security Administrstion has calculated the number at 0.3%
Upon further investigation I discovered that the CPI-W for July and August 2016 had been retroactively adjusted downward slightly thereby affecting the COLA calculation just enough to discount the rounding to 0.4% as I originally calculated.
Original post today:
The CPI-W for July 2016 was at 234.789. The August CPI-W was 234.909 and for September it was 235.495. Thus the average for the third quarter of 2016 is 235.064
The average for the previous benchmark of July, August and September 2014 (last year of a COLA December 2014/January 2015) was 234.241.
A difference of 0.35 or rounded to 0.4%
Therefore the 2017 COLA is 0.4% so if your monthly benefit is $1,300, your benefit will increase by $5.20 but because of Medicare premiums going up, the typical beneficiary will see no increase in their Social Security net income.