jipp curve is a term for a graph plotting the number (density) of telephones against wealth as measured by the gross domestic product (gdp) per capita. the jipp curve shows across countries that teledensity increases with an increase in wealth or economic development (positive correlation), especially beyond a certain income. in other words, a country's telephone penetration is proportional to its population's buying power. the relationship is sometimes also termed jipp law or jipp's law.