Yes, when you have lump sum payments for prior years, the information is used to calculate your tax as it would have been if you had received that lump sum in that earlier year.
You can try calling the Social Security Administration and asking for a complete breakdown, or you can just report the information that you were given and leave the rest of it to be taxed at this year's rates.
In other words, report the specific amounts listed for the specific years and ignore the "Other years" entry.