Whole different test, different questions, completely different content. They never give the same one twice.
And the content is much harder, not easier. Kids today are asked to know much more math than we did -- it's a tech world, folks. I had high scores back in my day, but doubt seriously I could do well today.
Another factor impacting SAT stats is that many more kids are taking it. Remember when you needed a high school diploma to get a good job? For most of today's kids, it's a college diploma, even though reality suggests that not all of us are college material. But they're still urged to take the test, and those low scores pull overall stats down.
Anybody can register for the SAT. I strongly suggest that some of the folks blowing hard on this thread go take it themselves and report their scores back to us.
As for more kids taking the exam, than in the sixties, no way. College was a draft deferment- everyone went, or at least the boys. I always thought that Community Colleges proliferated at this time, just to handle the kids with low SATs that wanted the deferment.
I hesitate to mention this, because you're going to think that I'm nuts, but I used to do my son's SAT prep material on the computer, for the fun of it. Unfortunately, I've forgotten most of the math, that I once knew, and a lot of the grammar. The test would be impossible for someone who has been out of school and away from academics as long as I have been.