Apple's stock has seen a rough summer, dropping from 132 to 114 in just a couple of weeks. As its volatility has been increasing, the tech giant's effect on the broader Nasdaq 100 index is also growing.
Through Tuesday, Apple's weight in the index was 12.99 percent, but it's contribution to short-term risk was 17.04 percent.
Those numbers are from Axioma, a firm that creates tools to help portfolio managers with risk modeling and investment strategies. Axioma's risk measure is a forecast for how volatile the stock will be relative to the overall index in the next two months.
The 17 percent risk number is in line where it was last week—at 18 percent, but higher than where it ended the last two years: