Experimenting with limited introduction of free-market forces into the economy, Laos has attempted to reform its trade and investment regimes, particularly in order to join the World Trade Organization. However, tariffs remain high, and non-tariff barriers substantially affect trade flows. In a notable move toward opening up the economy, the government sold stakes of about 30 percent in two state-owned companies through initial public share offerings and listed the shares on the Lao Securities Exchange, which came into operation in 2011.