Celebrating most are those who deferred, or will defer, Social Security to age 70. They will get the biggest possible increase in their monthly benefit check.

The lesson: if possible, defer your Social Security benefit to age 70, to maximize your monthly retirement paycheck.

A brief reminder of how Social Security works:

• You and your employer pay into the system via payroll deductions throughout your working life.
• You can generally take your monthly benefit as early as age 62 or as late as age 70.
• If you wait to take Social Security until age 70, you lock in a benefit that is almost double what you would receive from age 62. Every month you wait, up to age 70, locks in a slightly higher benefit for life.
• That benefit increases annually with inflation.
• You receive the monthly check for as long as you live. If your spouse made more than you, you get the higher of 50% of your spouse's benefit or 100% of your benefit. When one spouse passes away, the survivor gets the higher of the two benefits.

There are all kinds of additional rules, which we won't cover here. They address situations like death, divorce, remarriage and disability.

The key point: Social Security is great protection against running out of money in your 80s or 90s. It will always pay, and it will go up with inflation. That's hugely valuable. If you can boost your monthly check by delaying gratification - that is, by waiting until age 70 to take your benefit - you have created even more of a cushion.

Admittedly, waiting to age 70 is not the best decision for everyone. When both spouses have worked for many years, it sometimes makes sense for one spouse to take the benefit early. If you expect a shorter than average life, waiting may not be optimal.

But the risk most people need to guard against is running out of money late in life - especially as more of us live into our 90s. A larger Social Security benefit is worth the wait.