Measures mid-cap stocks that exhibit growth characteristics. This is a market cap weighted index including a selection of securities chosen from the Wilshire Mid-Cap 500 Index with growth characteristics as defined by Wilshire. The index is an excellent way to evaluate this sector of the market and to gauge the performance of managers focusing on this particular style. An equal weighting of this index, along with the Wilshire Mid-Cap Value Index, results in approximately the same return as the Wilshire Mid-Cap 500 Index.

• The Wilshire Mid-Cap 500 Index is equally divided into growth and value indices by market capitalization weight, not number of stocks.
• Growth and value is defined by looking at two factors: price-to-book ratio and price-to-earnings ratio.
• Earnings is not the trailing twelve months' earnings, but instead the projected analyst earnings for the next year as provided by Institutional/Broker/Estimate/Service.
• Price-to-book ratio is given three times the weight of price earnings in the calculation of individual stock "style scores" because price-to-book is a more accurate identifier of growth and value stocks.
• Stocks are then ranked according to their style score from the highest growth (lowest value) to the lowest growth (highest value) score.
• Stocks with the higher growth style scores comprise the Wilshire Mid-Cap Growth Index until their capitalization reaches half the total capitalization of the Wilshire Mid Cap 500 Index.

• Additions to the index are made once a year in June.
• A security will be excluded from the index at the month-end following the day it stops trading.
• Shares outstanding may be adjusted to reflect corporate events during the quarter; otherwise, shares outstanding are updated once a quarter.