The time series is measured according to the international standard for official development assistance (ODA) determined by the OECD Development Assistance Commitee (DAC). ODA is defined as aid provided by official agencies that the economic development and welfare of developing countries. ODA flows for biodiversity are recorded using the socalled “Rio markers”. These relate to the Rio Conventions on climate change, biodiversity and desertification. For each ODA activity it is indicated whether it targets the objectives of the Rio Conventions as a ‘principal’ or ‘significant’ objective. Activities marked ‘principal’ would not have been funded but for that policy objective, activities marked ‘significant’ have other primary objectives but help meet the policy objective. Hence the markers are considered descriptive rather than strictly quantitative.