Nevada is the sole state where retirees eke out a comfy living; its retirees replacing 71 percent of their working incomes.

But wait — the good news is also the bad news, since, according to experts, part of that more comfortable replacement income is more likely due to seniors working later than 65, rather than to 401(k)s or Social Security. With more seniors working later in life, their incomes are up a bit from what they were a few years ago. But it's not due to retirement benefits; it's due to jobs. 

In fact, the percentage of seniors working past 65 has been on the increase for the last two decades. This past May, it hit 18.9 percent — one of the highest levels in the last 50 years, according to the study. 

To come up with the results in its study, Interest.com divided the median annual household income for those who are 65 and older by the median annual household income for those between 45 and 64 years old, based on U.S. Census data, for each state and for Washington, D.C. 

Here's a look at the 10 states where retirees have it toughest, and how much they're in the hole. 

1. Massachusetts. Retirees have a hard time making it in the Bay State, with a median income of only $40,020 compared with median incomes of $82,221 for those between 45 and 64 years old. That's only 48.74 percent of what the younger folks make, a far cry from the 70 percent experts say they need to get by. 

2. North Dakota. Marginally better than Massachusetts, North Dakota is still a challenging place to retire, moneywise. Retirees' median income here is even lower at $35,293, although so is younger people's annual income of $72,043. But the percentage is higher by a hair, at 48.99 percent. 

3. Minnesota. Cold states seem to be cold toward retirees. Older Minnesota residents only make $38,531; that's only 51.87 percent of younger folks' $74,284 — coming up short of what they need. 

4. Connecticut. Seniors need to have strong constitutions to be able to make do with 52.20 percent of their working days in the Constitution State, bringing in median incomes of only $44,240. Younger people make a median of $84,757. 

5. New Jersey. Retirees in the Garden State had better have retirement vegetable gardens, if they're going to get by on only 52.57 percent of younger folks' median $85,778. They have to stretch their own median $45,092 pretty far — maybe they can spend some of that retired time off fishing at the beach. 

6. Wisconsin. How cheap is cheese in America's Dairyland? Retirees probably know to the penny, since their median income of $34,721 is only 53.78% of younger people's median annual $64,563. Still, grilled cheese sandwiches cost less than lots of other foods … 

7. New Hampshire. At 54.26% of what younger people make — $78,157 — the Granite State can be pretty hard on retirees, who only make a median of $42,406. Maybe they can nip over the border to see if things are any cheaper in Canada? 

8. Pennsylvania. The Keystone State is certainly not the key to a comfortable retirement, even if working people's median income is lower than in other states at $64,401. Retirees still need 70 percent of that, but they only get 54.36% — which amounts to just $35,009. 

9. New York. Is anybody surprised that the Empire State is on the list? Actually, considering that it's the home of Wall Street, the surprise is that younger people's median annual income is only $68,696. But retirees are still coming up short, making nowhere near close to it at only a median of $37,769. 

10. Rhode Island. Little state, little retirement income. Seniors only make 55.15% of what they need, a paltry $39,577 median income, compared with younger people's $71,756. Still, maybe they could take a page from New Jersey and go fishing.