MP Materials Corp. ( MP - Free Report ) shares rallied 9.5% in the last trading session to close at $31.17. This move can be attributable to notable volume with a higher number of shares being traded than in a typical session. This compares to the stock's 20.3% loss over the past four weeks. MP Materials' shares have surged on the announcement that the S&P 500 is adding the stock to its MidCap 400 index of companies, effective Jul 27. This company is expected to post quarterly earnings of $0.36 per share in its upcoming report, which represents a year-over-year change of +140%. Revenues are expected to be $124.74 million, up 70.6% from the year-ago quarter. While earnings and revenue growth expectations are important in evaluating the potential strength in a stock, empirical research shows a strong correlation between trends in earnings estimate revisions and near-term stock price movements. For MP Materials Corp., the consensus EPS estimate for the quarter has remained unchanged over the last 30 days.