Indeed. It changes based up on the fixed rate they set, and based upon the current level of inflation. The higher inflation goes, the higher the interest rate goes. The attached chart shows the current interest rate as of 1/11/22, and every interest rate dating back to 1998.
I dipped my toe in the water back in September and bought $1050 in i-bonds when the interest rate was 9.62%. If I'm understanding correctly, that should add $606.06 to my bonds in March 2023 ($101.01 per month, paid out every 6 months), and then the new interest rate will take over and add another $684.62 in September 2024 ($114.10 per month), totaling $2340.68 on my $1050 investment after just one year. I'm doubting my math, though, because this seems insane... What could the government possibly get out of this deal?