Ducky

Conversion of financial transactions to footprint

Get footprint in kilograms of CO2-equivalents for financial transactions by category

All inputs, outputs and defaults can be seen in the Convert finance technical API docs.

Inputs

This endpoint receives:

  • a data source to base calculations on
  • a list of financial categories, associated with a value of money spent and unit of currency
  • optionally: the date for which the footprint should be computed

At least one category must be provided. Value and unit of currency is optional; we accept all major currencies as input If you have not submitted a value, you will receive the footprint of 1 unit of the given currency, for the selected data source. The date the financial transaction took place is also optional input. If no date is given, the current date is taken as default.
dataSource Valid input unit of currency
norway NOK
japan (planned) JPY (planned)
united_kingdom (planned) GBP (planned)
finland EUR
sweden SEK
denmark DKK

Outputs

This endpoint returns, for each category:

  • footprint in kilos of CO2e, rounded to grams

Categories

The table below details the categories accepted by the Convert Finance endpoint. The “Lvl” field refers to the level in Ducky’s category hierarchy. Only level 2 and 3 categories are available in Convert Finance, as higher level categories do not provide useful enough detail. The field “COICOP identifier” is the code for the corresponding Classification Of Individual Consumption By Purpose (COICOP) category; if you are unsure what category a purchase belongs in, you may refer to the COICOP documentation to look for a suitable match. All COICOP level 2 categories are covered, while level 3 categories have been added in areas that benefit from a higher level of detail. This applies to e.g. passengerTransportServices - since different modes of transport have very different footprints, we have further subdivided this category into transportRailway, transportRoad, transportAir and transportWater. Additionally, we provide a suggested mapping of Ducky’s categories to merchant category codes (MCC) categories upon request.

Ducky currently supports two different versions of the COICOP system, 1999 and 2018. Users can choose categories from either or both revisions, but are advised that the 2018 will produce more up-to-date results. The table below shows which categories are available in which version.
Category name 1999 2018 Lvl COICOP identifier (2018) Description
food x x 2 011 Food and edibles purchased for consumption at home
nonAlcoholicBeverages x x 2 012 juices, water, soft drinks, coffee, tea
foodProductionServices n/a x 2 013 Services for processing primary goods for food and non-alcoholic beverages
alcoholicBeverages x x 2 021 beer, wine, spirits and liquor
alcoholProductionServices n/a x 2 022 Services related to producing alcohol in households
tobacco x x 2 023 cigarettes, cigars, other tobacco products, other narcotics
narcotics n/a x 2 024 All narcotics, natural and synthetic
clothing x x 2 031 clothing materials, garments, and tailoring, repair and cleaning services
footwear x x 2 032 footwear and repair and cleaning services
actualRentals x x 2 041 payment for rental of land, residences both primary and secondary, and connected parking spaces
imputedRentals x x 2 042 the economic value in rental equivalent of dwellings that are owned by their residents. Not the same as e.g. mortgage
homeMaintenance x x 2 043 materials for regular home maintenance such as paints, plumbing items & fire extinguishers, security equipment, and services related to regular maintenance
homeServices x x 2 044 water supply, garbage, sewage collection and similar services
waterSupply x x 0441 Water supply
refuseCollection x x 0442 Refuse collection and disposal
energy x x 2 045 electricity, gas and other fuels
energyElectricity x x 3 0451 electricity from all sources
energySolidFuels x x 3 0454 solid fuels such as firewood, coal, etc
furniture x x 2 051 furniture including garden furnitures, furnishings such as light, loose objects such as carpets, art and clocks, and repair and installation of such items
textiles x x 2 052 household textiles such as curtains, bedding, towels, doormats; repair of such items
appliances x x 2 053 major household appliances such as refrigerators, dishwashers, ovens, vacuum cleaners and air-conditioners, and repair and installation of such items
tableware x x 2 054 glassware, cutlery, flatware, silverware, kitchen utensils and other small household items; repair of such items
houseAndGarden x x 2 055 motorised tools like drills and lawn mowers, small hand tools for house and garden, and repair of such items
householdMaintenance x x 2 056 expendendable household goods like soaps and polishes, cleaning implements, napkins, and disposable kitchen goods; glue and tape
medicalSupplies x x 2 061 medicines, vaccines, medical devices, and other medical products including assistive products like hearing aids or crutches; repair and maintenance of such items
outpatientServices x x 2 062 all medical services that don't require an overnight stay, including dental work and long term assistive care
inpatientServices n/a x 2 063 all medical services that require an overnight hospital stay
healthServices As hospitalServices x 2 064 diagnostic imaging services and medical laboratory services; patient emergency transportation services and emergency rescue.
vehiclePurchase x x 2 071 purchase of vehicles for transport including cars, motorcycles, bicycles and animal-drawn vehicles
operationOfTransportEquipment x x 2 072 parts and accessories for personal transport equipment such as tires, inner tubes, batteries, helmets, GPS, roof boxes, etc
fuelsForTransport x x 3 0722 petrol (gasoline), diesel, liquid petroleum gas, lubricants; electricity as a fuel when separately priced from other electricity
maintenanceOfTransportEquipment x x 3 0723 services related to maintenance and repair of personal transport equipment; includes parking & tolls
passengerTransportServices As tranportServices x 2 073 all transport services public and private
transportRailway x x 3 0731 passenger transport by railway, rapid transit or tram
transportRoad x x 3 0732 passenger transport by road, including buses (regular routes, charter and school buses), taxis or hired cars, tuk-tuks, motorcycle taxis
transportAir x x 3 0733 passenger transport by air, any distance
transportWater x x 3 0734 passenger transport by water, including ships, boats, ferries, hovercraft, hydrofoils and water taxis
goodsTransportServices As postalServices x 2 074 stamps, courier services, parcel delivery, delivery of goods
itEquipment As computerEquipment x 2 081 Telephones, laptops, computers, printers, and other communication equipment
software n/a x 2 082 Software excluding games
audiovisualEquipment x n/a 2 n/a TV, cameras, recorded media like CDs, software
itServices As telephoneServices x 2 083 installation and subscription costs or fees for internet and phones; subscriptions to streaming services or TV
recreationalGoods x x 2 091 Items such as cameras; camper vans, boats, horses, golf carts, billiard and ping pong tables
sportingGoods x x 2 092 equipment for sport, camping and open-air recreation; games and toys
gamesGardensAndPets x x 2 093 Garden products; pet and pet products
recreationalServices x x 2 094 rental, maintenance and repair of recreational items, as well as veterinary services, tickets to sporting event, fairgrounds or theatre, and membership fees to recreational services; gambling
culturalGoods n/a x 2 095 Musical instruments and media like CDs or tapes
culturalServices n/a x 2 096 Cinemas, theatres, museums, photographers; repair of cultural goods
newspapersAndBooks x x 2 097 all kinds of books in physical and electronic form, recorded tapes/CDs/DVDs, newspaper and other periodicals, stationary and misc printed matter like brochures
packageHolidays x x 2 098 all-inclusive holidays or tours
preAndPrimarySchool x x 2 101 kindergarten and primary education
secondarySchool x x 2 102 secondary education
vocationalSchool x x 2 103 post-secondary non-tertiary education; preparation for labour market entry
universityAndCollege x x 2 104 higher education such as universities or colleges
otherEducation x x 2 105 education not defined by level such as language courses or tutoring and driving lessons
catering x x 2 111 food purchased for consumption outside of the home such as restaurants, cafeterias, cafés, vending machines or cinemas; includes tips
accommodation x x 2 112 resorts, hotels, hostels, rental cabins, guesthouses, dormitories or railway sleeping cars
insurance x x 2 121 all types of insurance including life, health, dwelling and transport
financialServices x x 2 122 moneylenders and credit cards; fees for banking
personalCare x x 2 131 appliances such as razors or toothbrushes, including electric appliances, and repair of such items; make-up, hairdressing and salons
personalEffects x x 2 132 jewellery, watches, devotional/religious items, bags and purses; repair of such items
socialProtection x x 2 133 Non-medical assistance and support services to the elderly, disabled or destitute
otherServices x x 2 139 legal services, services for real estate agents, photocopies, administrative documents, and other personal services like astrologers or private detectives
donations x x 2 n/a all kinds of charitable donations

Calculations and sources

The footprint of a purchase is calculated by multiplying the transaction amount with the multiplier for the associated category.

The multipliers for level 2 categories are extracted from Exiobase 4, a multi-regional input-output (MRIO) table. An input-output table documents the economic activity by recording the flow of money in and out of different sectors of the economy.  “Multi-regional” simply means that the economy of many countries is included, so that imports and exports can be modelled accurately. Direct greenhouse gas emissions data is associated with each economic activity, and we can thus calculate the indirect emissions or footprint of money spent on a given good or service.

The multipliers for level 3 categories are calculated using a bottom-up approach, whereby Ducky obtains emissions based on life cycle assessment, and corresponding price and spending data, and uses these to calculate the emissions per unit spending.

In a very few cases, multipliers can be negative. Currently this is the case for the “homeServices” level 2 multiplier and the “refuseCollection” level 3 multiplier for some countries. This is due to allocation of waste in Exiobase - waste is sometimes recycled material which can be used in new products, replacing virgin material. Hence,performing certain home services or recycling waste can offset the manufacturing of a new material, which can lead to material and carbon savings, and  Iin this case the net climate impact is positive. The logic leading to negative multipliers is explained in detail on this webpage.

The date also influences the calculations, with the multipliers used in calculations being updated monthly. We account for inflationary effects, fluctuating prices on certain goods,  and changing technology over time.. For example, as manufacturers decarbonize their supply chains, the emissions intensity of their products will decrease. Hence, if you buy the same product five years from now, the footprint of your purchase will likely be lower.

See also intro to convert endpoint overview for related endpoints.