Why does the escape character not work when I try to print the % sign?

Question

I've already tried using the escape character \% but I always get the warning

more '%' conversions than data arguments [-Wformat]

Here's part of the bugged code:

int percent = 1;

if (income < 750) {
    printf("The tax amounts to the %d\% of your income\n\n", percent);
}

Thanks a lot for the help that you guys always give me