This study investigates the influence of the stock market on economic growth by extending the
Mankiw–Romer–Weil (1992) model to incorporate the stock market.1 Atje and Javanovic (1993)
augment the Mankiw–Romer–Weil (MRW) model with a variable for the stock market. They
examine the influence of the stock market on the level and growth rate of economic activity, and find
a large effect of the stock market on economic growth. The present study decomposes capital into
two components, non-stock market capital and stock market capital, and treats the stock market as a separate variable in the production function which differentiates it from the Atje and Jovanovic
study. The level and growth effects of the stock market on economic activity are considered as in
the Atje and Jovanovic study. The structural parameters of the model are also estimated. Finally,
policy implications are examined. Thirty-five developing markets are used to test the stock market
augmented model. The study employs three stock market indicators to measure stock market
development: market capitalization, market liquidity and the turnover ratio. A composite stock
index that incorporates stock market size, liquidity and activity as constructed by Demirgüc-Kunt
and Maksimovic (1996) is also used. The developing stock markets are used as a basis for this
study given the significant expansion in the stock markets of these economies in the recent past.
Market capitalization as a % of GDP in the emerging economies have grown from 18.8% in 1990
to 33.3% in 2002, value traded as a % of GDP (market liquidity) from 5.2% to 17.8% and the
number of listed companies from 774 to 3132 in the same period (World Bank, 2004). Portfolio
equity investment flows into these market have risen from US$ 3390 million in 1990 to US$ 37,559
million in 2004 (World Bank, 2006). According to Levine and Zervos (1996) developing country
stock markets comprise a disproportionately large amount of the growth in world stock markets.