Of all 23 developed nations. That's from OECD international testing. Why? Because USAAmeruca is horrible at teaching math concepts. Only 8% of us are proficient at numeracy, meaning, understanding math concepts well enough to apply them in various situations.
What we're good at is plug and chug, I.e. taking a formula, putting in numbers, and churning out an answer. It's garbage pedogogy, and it's designed to create dumb asses who cannot apply basic math.
As a physics student, not one thing ever explained why the fuck calculus was created, why it supplements the sciences, or why it's necessary. Didn't matter if you went to catholic school or not, all of my math teaching was premised on doing problems, with NO discussion of the concepts, or why the subject is necessary in the first place.
I'll let you in on something that will underscore how fucked and corrupt USAAmerican schools are. All the math you'll ever need, and I mean all the way to STEM grad school, was when you learned fractions, ratios, and percentages. Those are "pure numbers" and if you're thinking you've never heard of such a thing, yes you have. Pure numbers are trig functions, all of geometry, slope of a line, integrals and differentials, exponents, logs, thermo entropy, and a bunch of other things. That inventory alone tells you the importance of pure numbers. I challenge anyone to find a traditional math textbook that will tell you that basic fact, and go into a detailed discussion as to the vast importance of the pure number. All statistical and marginal analysis is premised on that one concept. I had to learn it on my own when I was doing physics research as an undergrad. Pure numbers are essential when you set up your experiment, establish initial conditions and record as much info about those ICs, introduce a catalyst into the beginning system, then measure what happens afterward. That's why math and pure numbers were created, to measure the results of changes. Bada boom, bada bing. That's all the fuck it is. Anyone of normal intelligence can easily understand that, because it makes common god damn sense.
You're not a math idiot, you're just a product of a school system that had no interest in creating well educated, critical thinking citizens. The only two teachers worth a damn at my Jebbie high school said as much. Both eventually left the church when they had had enough...