Have you heard of PISA? No, it’s not some delicious Italian dish you can buy in a restaurant. It’s the preeminent international assessment of student performance in more than 70 countries across the world. A project of the Organisation for Economic Cooperation and Development (OECD), PISA is administered to a representative sample of 15-year-olds in these countries every three years.

Sadly, the recently released results of the 2015 PISA assessment are significantly harder to swallow than tasty Italian food.

For those of you who are particularly wonky, you can find the full report on the most recent PISA results here. Other folks may prefer to surf OECD’s curated topline results and interactive map, which can be found here. If you are culturally insensitive and only interested in the results for the United States, those can be found here. If you really, truly don’t want to be bothered with all those numbers, don’t fret. We’ll cover the big stuff right here in this post.

Quick refresher: A couple years ago, the 2012 PISA results showed us that the U.S. ranked below average in mathematics, coming in 27^th in among the 34 members of the OECD. Those members are largely considered to make up “the developed world,” and are the countries we are most directly competing with in the global economy. We ranked 17^th in reading and 20^th in science, both of which were roughly in line with the OECD average.

Interestingly, the 2012 PISA report also noted that despite our depressingly mediocre academic performance, only four other nations—Austria, Luxembourg, Norway, and Switzerland—spent more per student than the United States. Meanwhile, the Slovak Republic ($20 to the first person who can find this country on an unlabeled map) spent about half as much per student and performed at the same level. Korea, which topped the 2012 chart in mathematics, also spent well below average amounts per pupil. It’s almost like there’s more to education than spending more money on it…

One would hope that three additional years of work would lead to better results on the 2015 PISA. One would be wrong.

In the words of AEI’s Rick Hess, who had some interesting thoughts on this year’s results, the 2015 PISA results are “ugly.”  The U.S. still shows dishearteningly mediocre results. In fact, we performed somewhat worse in 2015 than we did in 2012.

There are now 35 OECD members (Latvia snuck in this past July). Within that list, we’ve seen very little positive movement. The U.S. remains average in reading and science, ranking 20^th and 19^th, respectively. We’ve moved up one spot in the science rankings, but that’s not really cause for celebration given that we haven’t seen a statistically significant change in science performance since 2006. Our rank has worsened in reading, but we haven’t seen any significant performance changes on that front since 2009.

There’s basically nothing to see when it comes to reading and science performance. We’re still average. And that’s still not good enough.

Unfortunately, the news only gets worse from there. Our math performance fell off something of a cliff between 2012 and 2015, with our mean scores in science plunging from 481 to 470. Eleven points may not seem like much, but that’s a pretty big drop when it comes to PISA. We already performed below average in math, and now it seems we’ve fallen further from where we should be. Correspondingly, our ranking for math scores has slipped to 31^st out of 35 countries.

There’s some variation in our rankings in each subject once measurement and sampling error are accounted for, but not enough to change the overall takeaway of the U.S.’s 2015 PISA results: We should be doing much, much better.

The icing on the cake is that we still spend far more per pupil than most other countries. We now spend less than five countries instead of four in exchange for our disappointing results, but the fact remains that our education system does not appear to be a model of fiscal efficiency.

I know what you’re all asking yourselves: What’s going on? Why aren’t we improving? What’s holding us back? The short answer is that it’s hard to say. As is the case with NAEP scores (warning: this post contains the infamous graphs over which I had a big, nerdy spat a year ago), it would be a mistake to attempt to attribute our continued poor performance on PISA to any particular policy or variable without a lot more information. That’s not how statistics work, and it’s not how we should go about the business of having productive education conversations.

For now, we’ll have to take the results for what they are: an indication that we have an awful lot of work to do if we want our education system—and the adults it produces—to be able to compete on the global stage.