Since you don't need to submit a scatter plot, you can just look at the table and see if you want to use an exponential graph or logarithmic graph. First, you need to know the properties of the two graphs. An exponential graph has pretty slow growth at the beginning, and then rapid and extremely fast growth toward ∞. On the other hand, ㏒(x) function starts out very fast but slows down as it gets closer to its asymptote and then it's the slowest thing ever.
This data starts out on a relatively big jump in 6 years, then it grows just a little (because the log(x) function is like that remember) and then it slows down a whole lot. In fact, from a rate 19.67 from the first two years to a rate of 6 in the last two years. So, it would be ideal if you use the logarithmic function - it is the best choice for graphing this data. This is how I would work through it :)