Final answer:
To find the percent decrease in population per year, multiply the difference between the current population and the next year's population by 100.
Step-by-step explanation:
To find the percent decrease in population per year, we can use the formula: percent decrease = (1 - 0.971) * 100. This formula calculates the difference between the current population (1) and the next year's population (0.971), and then converts it into a percentage.
For example, if the current population is 100, the population next year would be 100 * 0.971 = 97.1. The percent decrease would be (1 - 0.971) * 100 = 2.9%. So, the population decreases by 2.9% per year.