Here are some examples:
Income/annual SS deductions from paycheck/amount paid in over 40 years/total at 2% return/total at 10% return/amount paid to you over 18 years in retirement
20,000 2,880 115,200 224,350 3,076,607 193,000
100,000 14,400 576,000 881,332 7,588,895 772,520
And that is if you survive to collect anything at all.