IJT is the oldest of 3 ETFs tracking the S&P SmallCap 600 Growth Index (the others are VIOG and SLYG). The index uses three growth factors: three-year change in earnings per share over price per share, three-year sales per share growth rate and momentum (12-month percentage share price change) to select stocks with the best growth characteristics, and weighs them according to market capitalization. Blackrock uses a representative sampling indexing strategy to manage the fund and may or may not hold all of the securities in the Underlying Index. The index is rebalanced once a year.