The Russell 2000 has risen at nearly double the rate of the S&P 500 this year as more investors are flocking to small-cap stocks, and there are three reasons shareholders have done so, according to Lee Munson, Chief Investment Officer of Portfolio Wealth Advisors.

Munson said investors are being sold on the idea that buying small-cap stocks will take advantage of the loose regulatory environment, avoid the effects of a trade war and the dollar fluctuations that are "hurting" multinational corporations.