The RCAComplexity diagram compares the Revelead Comparative Advantages of states in Pebbles, Gravel, Crushed Stones, of a Kind Commonly Used for Concrete Aggregates, for Road O, Railways or other Ballast, Shingle and Flint, Incl. Heat Treated and the Economic Complexity Index of each state.. RCA values greater than 1 indie that the state has comparative advantages in Pebbles, Gravel ...