Poverty continues to be strongly linked to food insecurity. As one of the poorest countries in the world, around 43.7% of its population lives under the Poverty Line Burkina Faso ranked 185 out of 188 countries on the UNDP Human Development Index in 2015. The Human Development Index is a measure of quality of life, taking into account three main areas of human development: longevity, education, and economic standard of living. These high levels of poverty found in Burkina Faso, combined with the soaring food prices of the global food crisis continue to contribute to Burkina Faso's issue of food insecurity. The global food crisis of 2007–2008 was a drastic surge in food prices that led to high rates of hunger, malnutrition, and political and economic instability in nations across the globe. This strongly affected Burkina Faso because around 80% of Burkina Faso's population is rural, relying on subsistence farming to make a living. For instance, when natural disasters such as floods, droughts, or locust attacks occur and cause crops to fail, farmers in Burkina Faso become dependent on grain purchases. Because of the global food crisis, local grain prices dramatically increased, limiting farmers' access to grain through market exchanges.