Can someone help me translate To measure just how concentrated stock returns have been, we calculated the impact that the 10 largest stocks have had on the Mor

Can someone help me translate To measure just how concentrated stock returns have been, we calculated the impact that the 10 largest stocks have had on the Morningstar US Large-Mid Index, which essentially tracks 90% of the stock market. We took the 10 largest stocks at the end of each year going back to 2009, and using Morningstar Direct's equity attribution tool, excluded their returns from the index's performance and compared that number with each year's total return. into mathematics so I can interpret the percentages in the table below? Why do people involved in finance hate mathematics so much? Is it obvious to everyone? EDIT: I think it is: returns_of_index_per_year - returns_of_index_minus_returns_of_top_N_stocks_per_year EDIT 2: What does "Cumulative Market Impact" mean? When you google it or "Market Impact" it gives bunch of unrelated measures... Finance jargon is such a mess.