Here is a sentence from the.
McGraw Hill conquering GMAT Verbal & Writing.


Economists fear that without a substantial increase in the amount of contributions
households make to their retirement funds, more than of third of them will not
be able to live as well in retirement as today.

the answer below..

Economists fear that without a substantial increase in the amount of
contributions households make to their retirement funds, more than of
third of them will not be able to live as well in retirement as they do
today.
The comparison is between how they will live in retirement and
how they live today. The second part of the comparison needs a
verb to maintain parallelism.


however in the answer a couple of things do not seem to sound good.

-> of third of
-> "them" is pointing to "households" or "retirement funds"
can somebody plz explain.