Total US butter consumption

It appears that Americans have been engaged in a seventeen-year campaign to trade butter for drowning, a substitution so perfectly inverse it suggests either a vast aquatic conspiracy or the universe's most elaborate joke about cholesterol management. The correlation is nearly perfect, which is to say that as the nation collectively decided to consume less butter, it simultaneously became better at not dying in swimming pools. One wonders if the butter knew.

What's actually happening here is considerably less sinister and considerably more banal. Swimming pool drowning deaths have declined over this period thanks to better supervision technology, CPR training programs, and basic learning about water safety—boring, effective stuff that happens to correlate with broader economic and health consciousness. Meanwhile, butter consumption fell partly due to the low-fat diet craze of the 2000s, partly due to shifting consumption toward plant-based oils, and partly because Americans got distracted by other fats entirely. These are two different stories wearing the same hat, like watching someone lose 40 pounds and sell their car in the same year and deciding the car must have weighed 40 pounds.

The thing about butter and drowning is that they're both genuinely declining—the data is real, the correlation is absurdly tight, and yet they have almost nothing to do with each other. This is what makes pattern-seeking such a seductive hobby: the universe will occasionally hand you something that looks exactly like proof of connection, and you'll spend weeks wondering about it before realizing you've been fooled by coincidence. The butter consumption data doesn't know about the pools.