You seem to have run every scenario for when to take social security except mine .I am eligible to collect survivor benefits at 60 on my late husbnd's social security and then switch to mine at either 62 or wait till 66.The difference between the survivor benefits and mine at 62 is $300.00 a month .The difference at 66 is $700.00 a month .What should I do ? I have plenty of savings so it's not like I need the extra money but I also don't want to lose out .Without either of the higher amounts Firecal says I'm good for 95 years.
This is interesting. I've said that the general rule for single people, who don't need SS to pay the necessities, is to take it early. However, your case isn't "when to start" but "when to switch". It seems to me like you would defer.
First, I want to get the numbers right. It looks like your benefit as a widow has been $900 per month. If you switch to a retirement benefit based on your wage history, your benefit would be $1,200 per month starting at age 62 or $1,600 per month starting at age 66. (This set of numbers explains the $300 and $700 you're specifying, and is consistent with the 25% reduction in SS benefits if you start at 62.)
So suppose you have a twin who's identical to you in all respects, except that she switches to her own benefit at 62 and you wait till 66.
Ignoring interest and inflation, she will have more $300 x 48 = $14,400 more in her bank account (or investments) at 66 than you will.
However, once you start taking your benefit at 66, you'll close the gap at a rate of $400 per month. Now $14,400 / $400 = 36, so in 36 months you will be even. After that, you pull ahead.
( Doing the math a different way, between 62 and 69 she'll collect a total SS benefit of $1,200 x 84 = $100,800. You will get $900 x 48 + $1,600 x 36 = $43,200 + $57,600 = $100,800. )
After age 69, you'll continue to pull ahead by $400 per month or $4,800 per year. Since about half of 62 year-old women will still be alive in their low 80's, it seems that you're very likely to live long enough to "out collect" her.
If this were a closer call, it would make sense to look at the extra investment income she will earn while she's ahead. If she could earn a level 8% per year, her lead at age 66 would be around $17,000. But if you crunch the numbers, you'll discover that you still catch her at age 70. (Technically, she'd have to earn 8% plus inflation, but that seems like overkill for this decision.)
So, unless I've missed something pretty big, I think you'd be better off waiting till 66.