The phrases "in the years 1990, 2000, and 2010" appeared in my essay topic. Can I use something like "over the period of twenty years from 1990 to 2010" in the place of that phrase? I wonder if they are the same since they used "in three different years" and "over the three years shown" in the model answer. "The charts below show degrees granted in different fields at the National University in the years 1990, 2000, and 2010. Summarise the information by selecting and reporting the main features, and make comparisons where relevant."