Methodology and Sources
Global Footprint Network’s core research calculates both the Ecological Footprint, the demand on nature, and biocapacity, the capacity to meet this demand, of more than 200 countries, territories, and regions. The results, updated annually, as well as the calculations are shown in Global Footprint Network's National Footprint Accounts. The 2015 National Footprint Accounts use more than 6,000 data points for each country, each year, derived from internationally recognized sources (see data sources, below) to determine the area required to produce the biological resources a country uses and to absorb its wastes, and to compare this with the area available. This area is reported in global hectares (global acres), hectares (acres) with world-average productivity, for each year from 1961 through 2011.
The Ecological Footprint uses yields of primary products (from cropland, forest, grazing land and fisheries) to calculate the area necessary to support a given activity. Biocapacity is measured by calculating the amount of biologically productive land and sea area available to provide the resources a population consumes and to absorb its wastes, given current technology and management practices. Countries differ in the productivity of their ecosystems, and this is reflected in the accounts.
A nation’s consumption is calculated by adding imports to and subtracting exports from its national production. Results from this analysis shed light on a country’s ecological impact. A country has an ecological reserve if its Footprint is smaller than its biocapacity; otherwise it is operating with an ecological deficit. The former are often referred to as ecological creditors, and the latter ecological debtors.
Today, most countries, and the world as a whole, are running ecological deficits. The world’s ecological deficit is referred to as global ecological overshoot.
Calculation Methodology for the National Footprint Accounts, 2011 Edition describes the fundamental calculations and principles utilized in the 2011 edition of the National Footprint Accounts. It provides researchers and practitioners with information to deepen their understanding of the calculation methodology for the Ecological Footprint. It also includes calculation methodology for biocapacity, yield factors, equivalence factors, and the specific land use types included in the Ecological Footprint: cropland, grazing land, fishing ground, forest land, carbon uptake land, and built-up land.
The calculation methodology for the National Footprint Accounts 2011 edition has been published in the Ecological Indicators Journal (Vol. 24: pages 518-533), and a final draft can be downloaded here.
The actual implementation of the National Footprint Accounts through database-supported templates is described in the Guidebook to the National Footprint Accounts 2014.
Download the Working Guidebook to the National Footprint Accounts 2014 (6.9 MB)
Note: The resources linked to this section describe the methodology for calculating the Ecological Footprint and biocapacity at the national level. Since comprehensive global data sets on production and trade generally only capture data at the national level, the National Footprint Accounts serve as the foundation for all sub-national, organizational and product Footprint analyses.
The calculations in the National Footprint Accounts are primarily based on international data sets published by the Food and Agriculture Organization of the United Nations, United Nations Commodity Trade Statistics Database and other data from the UN Statistics Division, the International Energy Agency, and the Intergovernmental Panel on Climate Change. Other data sources include studies in peer-reviewed science journals and thematic collections. Of the more than 230 countries, territories, and regions analyzed in the National Footprint Accounts, 150 had populations over one million and were covered consistently by the United Nations statistical system.
Two committees, the National Accounts Committee and the Standards Committee, work with Global Footprint Network to respectively oversee the scientific basis of the National Footprints Accounts and standards for Footprint applications. In addition, the organization encourages national governments to conduct reviews of their country’s own accounts. Governments that have initiated reviews of the Footprint method and results include Switzerland, Japan, Germany, the United Kingdom, the European Commission and the United Arab Emirates.