Table: giorgio zampori
Question: In what year did Giorgio Zampori achieve the most overall success in World Championships?
Step 1 (Reasoning, Grounding): most overall success, number of 1st
Step 2 (Operation, Indexing): position	
Step 3 (Operation, Grouping): year	
Step 4 (Reasoning, Aggregating): COUNT, number of 1st events
Answer: 1913