Shedding light on the shadow economy : a nighttime light approach

Measuring the shadow economy is inherently difficult, but critical for understanding economic development. Using census data on formal and informal sectors in Cambodia, we document that 96.6% of non-farm establishments do not formally register with the government, and their sales accounted for 76.6% of total sales in 2011. We estimate a relationship between nighttime light and sales across regions separately for formal and informal firms for 2011, and estimate their past sales from changes in nighttime light for 1993-2010. Both formal and informal firms increased their estimated sales, and the share of informal sales increased from 68.8% in 1993 to 76.6% in 2011, suggesting that the informal sector increased quantitatively in both absolute and relative terms throughout the economic development of the Cambodian economy.