Don’t want to dissuade your decision if you’re set on taking the supplement. The extra 10% gained by staying to 62 is not the figure to compare to how many yrs it would take to “break even” to equal the supplement you could be receiving. By working 2 more years you would make a full salary for those 2 years and have 2 more years that you could contribute to tsp and also up your SS benefit. As an example consider if someone can get the supplement for 2 yrs at $15000/yr=$30K. Say they currently make $80K/yr. Next yr the 1.5% raise would bring it to $81.2K. So amount made in 2 yrs = 161.2K, which is $131.2K more than they’d get from the supplement. Sock $70K more in tsp with growth in those 2 yrs and it’d potentially make a big difference also. Now consider if their high 3 was about $78K. Their pension would be 20x.01x$78K=$15.6K/yr but in 2 yrs their high 3 might increase to say $80K which would then make their pension worth 22x.011x $80K= $19,360 or $3,760 more per year for the rest of their life. Last but not least 2 yrs can feel like forever or nothing at all depending on how you look at it.