Economics Matters — Blog/Podcast/Financial Riddler/MaxiFi Puzzler
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Riddle Me This
What country has the world’s lowest fertility rate?
a. South Korea
b. China
c. Taiwan
d. Singapore
e. Spain
And the answer is …
The 2025 answer is Taiwan — at .70. That’s only high enough for the moms to reproduce three quarters of themselves, let alone the dads. Taiwan nudged out South Korea’s .72 by a smidge. Singapore weights in at .87, China at 1.0, and Spain at 1.1. Iran’s is 1.45, just below Denmark’s 1.50 rate. Niger, at 6.73, has the world’s highest fertility rate. Meanwhile, the US rate fell to 1.57 from 1.62 in 2024. The biggest drop was among Hispanics — from 1.98 to 1.89.
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What is the longest range of any electric car on the market today?
a. 771 miles
b. 693 miles
c. 664 miles
d. 570
e. 497
And the answer is …
The answer is China’s 664-mile-range BYD Denza E9. The E9’s front seats provide full body massages and 16 different electronic adjustments. Frankly, I only need 13. There are also refrigerators in the front and back and fold out tables in the back. This is almost as cool as my dad’s 1958 Chrysler convertible. He bought it brand new. The record player worked for an entire week.
President Trump hates windmills — the ones that produce clean energy. He doesn’t want our country to look like Denmark, which has 6,980 of these babies. He keeps issuing executives orders to shut them down for national security reasons and to save the whales. Trump’s problem with wind turbines dates back to 2006 when he battled the Scottish government to stop an offshore wind farm from being built near his Aberdeenshire golf resort, claiming it would ruin the view. Personally, I think they are beautiful, especially compared to a coal-driven electric power plant. The President can be comforted, though, in knowing the US doesn’t have many of these “ugly monsters,” whose offshore presence is “Driving the whales crazy.” Who knew we elected a whale whisper. In any case, how many US wind turbines are there?
a. 1500
b. 1700
c. 2200
d. 3100
e. 57,000
And the answer is …
I lied to you. We have lots of these majestic machines — 57,000, in fact! On the other hand, Denmark has 7 times more wind turbines per capita than we have Stateside.
What was our nation’s net national saving rate in 2025? This is economics’ comprehensive measure of our country’s rate of saving. It’s the ratio of net national saving (gross saving less depreciation measured at producer prices) divided by net national income (GDP measured at producer prices less depreciation) For reference, the rate averaged 15.00% in the 1950s and 16.16% in the 1960s.
a. 21.78%
b. 17.81%
c. 12.12%
d. 5.34%
e. 1.48%
And the answer is …
The answer is 1.48%. Apart from the period of the Great Recession when the saving rate went negative, this is the second lowest national saving rate recorded since 1950. The rate in 2024 was 1.34%. Countries that don’t save don’t invest. In the 1950s and 1960s, our rate of net domestic investment averaged 13.45% and 13.77%, respectively. Last year’s investment rate was only 6.48%. Still, that’s better than 1.48%. So who invested last year beyond what Americans saved? The answer is foreigners. The 5.00 percentage point difference between our net domestic investment and net national saving rate reflects net foreign investment, which is called the current account deficit. Last year’s current account deficit was the third largest recorded since 1950. If you divide this figure by our saving rate you find foreigners are investing 4.4 times more in the US than Americans! In short, we’re on the path to Jamaica, with foreigners owning all the hotels and locals cleaning the rooms. With AI starting to displace our working force en masse and wealth becoming ever more concentrated, our country will, over time, be best described as a servant economy, not a service economy.
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What fraction of Americans with credit card debt have been in credit card debt for over one year?
a. 11%
b. 31%
c. 61%
d. 71%
e. 91%
And the answer is …
The answer is 61%, up from 53% in late 2024.
Can AI do economics-based financial planning or even Social Security benefit maximization right?
a. Yes
b. No
And the answer is …
The answer is a huge No. See this blog, this blog, and this blog. The leading LLMs, and there are now 70 plus to choose from, can’t even agree on the same wildly wrong answer. Nor can they reproduce the same wrong answer if you reword, just slightly, your question. Nor will they know to even do economics-based as opposed to conventional financial planning if you don’t prompt them to do so. What this tells me is that if you are using the wrong math to answer the right question you’ll always get the wrong answer. It also tells me that AI needs to be intensively trained on economics-based planning results before anyone should ask it anything about their finances. Finally, I’m wondering how long it will take for someone who has been given the wrong, say, life insurance advice to sue an AI company that recommended, say, half of what a decedent primary owner needed to sustain their family’s living standard.
The five-year cancer survival rate in the mid Seventies was 49% according to the American Cancer Society. What is it today?
a. 53%
b. 58%
c. 66%
d. 70%
e. 77%
And the answer is …
The answer is 70 percent.
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Is the S&P adjusted for growth in the economy at a post-1950 high?
a. Yes
b. No
And the answer is …
The answer is Yes. Here’s a chart of growth in the S&P adjusted for nominal GDP growth. And roughly 45% of the current value of the S&P is in AI-linked companies. This is why paying attention to what AI can’t do and may never do may be more important than paying attention to what it can do.
US S&P Adjusted for Inflation and Real GDP Growth
In 1970, 70% of recent high school graduates were enrolled in college. What is the proportion today?
a. 46%
b. 53%
c. 63%
d. 79%
e. 84%
And the answer is …
The answer is 63 percent and only 60 percent complete their degrees. Hence, just over one third of young American cohorts are becoming college graduates.
Before the Iran war, oil cost $70 a barrel. So far, during the war, it’s reached $120 a barrel. How high is it projected to rise if the Strait of Hormuz remains closed for at least one year?
a. $140
b. $160
c. $180
d. $200
e. $240
And the answer is …
The answer is $200 a barrel. This will put the price of a gallon of regular at roughly $6.50. If oil rises quickly to this level, 2026 inflation will likely equal 8 percent.
I'm 75 and a saver. Always have been. I tell young people to try and save 30% of their net income, if they can. Am I in the ballpark with that rate as I also tell them to get some financial planning advice from a professional and customize their investment needs over time?
Just because it worked for me I certainly don't want to steer anyone in the wrong direction.
It’s so easy