If we assume that today's population is 100, next year it would be 1.1 $\times$ 100 = 110, and the following year it would be 1.1$\times$ 110 = 121. If this is double the population of one year ago, the population at that time must have been 0.5 $\times$ 121 = 60.5. Because the problem seeks the "closest” answer choice, we can round 60.5 to 60.
In this scenario, the population has increased from 60 to 100 over the last year, a net increase of 40 residents. To determine the percentage increase over the last year, divide the net increase by the initial population: , or roughly $67\%.$