Answer:
This historian would find graphical data that exposed information about the causes of European imperialism during that period of time more useful.
Step-by-step explanation:
During the 19th century, European imperialism was one of the most important and influential economic factors, dominating much of the world economy. For this reason, a historian who was researching the economic systems in force at that time, would find great use in a graph that presented information about imperialism, mainly information that focused on the causes of imperialism at the end of this century.