#include <stdio.h>
int main(void)
{
        float sum; // beginning total of 1 million dollars
        const float x = 0.8;   // interest rate
        float new_total;
        float interest_earned;
        int year;

        for ( sum = 1000000, year = 0; sum >= 100000; new_total = sum - 100000)
                {
                        interest_earned = new_total * x;
                        new_total += interest_earned;
                        printf("year %d total funds in bank: %f\n",
                        year++, new_total);
                }

        return 0;
}