"I was just thinking about why your break even numbers differ from mine, and why my wife's break even numbers also differ."
There are some variables that may differ. The simplest calculation is that the $25,000 per year x 8 = 200,000 takes about 10.5 years to recoup at the $19,000 per year higher Social Security payments taken at 70 ($44,000) versus 62 ($25,000). That's the differential currently between the two choices. However, this differential may not stay a fixed ratio as whatever percent increase occurs in the future favors the higher payment. 2% of $44,000 is a substantially more than 2% of 25,000, and currently the percent increase is regardless of total payment. But the maximum payout could change, be capped, or taxed in the future.
The Social Security calculator may well use adjustments such as projected return on investment of the difference in payments over that 8 year period from 62 to 70. If they use such an adjustment, it would take longer to recoup the difference. This may be irrelevant in reality as most people do not invest their Social Security payments in part or whole. Then again, there is inflation. This is another adjustment they probably make based upon projections.
Just some educated guesses about why my calculations and yours and the SSA's may differ. Also, the differential between 62 and 70 at various levels of SSA payments may be more or less than I've shown for the maximum payouts. I've been fortunate and been able to work at jobs that exceed the maximal FICA contributions for most of my career.
I think it's fairly unlikely that it would take 16 years for most folks to recoup the difference between 62 and 70 but I don't know how those calculations were performed. The only thing that is certain is the 2018 payouts for you as an individual depending on your contributions, and the fact that annual payments are 8% higher for each deferred year after age 62.
You can do some rough math. If you would collect $25,000 per year at age 62 and 44,000 at 70, you need to recoup $200,000 for the 8 year difference. Assuming similar ratios over the years, you will need approximately 10-11 years (age 80-81) to recoup this amount at the differential of $19,000 more per year after starting at age 70 versus 62. This is obviously not entirely correct as no adjustments for inflation, investment, etc. have been made. And if you live only to 79, you never recoup entirely. Then again, if you live to 90-95, as a great many people will do, you've made out very well indeed.
Personal observation: in the 1970s there was almost no one in the NY Times obituaries who was age 90 or greater. Now, it is not unusual for there to be 3 of 3, or 2 of 3 deaths in their nineties in the on-line Times obituaries. Something extraordinary is happening with longevity for those make it into the last quarter or third of life. We do not know the explanation, but my own hunch is much, much cleaner air which reduces the risk of inflammatory diseases, including cancer, heart and vascular disease and respiratory diseases which account for 90% or so of deaths.