Final answer:
Excel automates data analysis for stock trading, allowing an economist to efficiently compare expected and actual stock market index points to evaluate the accuracy of a predictive model.
Step-by-step explanation:
Stock trading is especially reliant on Excel formulas because Excel automates the process of data analysis. An economist using Excel to predict stock market outcomes can leverage formulas to compare expected points on a stock market index with actual points at the close of each day's trading.
This comparison allows the economist to assess the accuracy of their predictive model by performing tasks such as calculating variances, generating charts, and applying statistical analysis with ease and efficiency. The automation of these processes can significantly reduce the time and potential for human error associated with manual calculations.