3. Data

Data comes from regular official statistical sources of CBS Statistics Netherlands on physical material flows (Material Flow Accounts, Waste Statistics) and the National Accounts. This allows statistical offices in other EU member countries (with data available at Eurostat) to use our methodology. Data is available annually for the period 1996-2022.

Material flows

Source: http://opendata.cbs.nl/statline/#/CBS/nl/dataset/83180NED/table?dl=25735. Updated data 2020-2022 (applied in this analysis) remain internal for now, and will be published in 2025.

Data on material flows comes from the economy-wide Material Flow Accounts (MFA). Material consumption is measured as Domestic Material Consumption (DMC), that is, extraction plus import minus export. DMC is a proxy for final (material) consumption (excluding export) of a country. ³⁾ Total DMC equals total consumption of biotic and abiotic materials (Prim). Biomass can be excluded from the DMC leaving only the abiotic materials (Prim_abiotic).

Figure 3.1 shows the development of the primary abiotic resource consumption (in megaton) between 1996 and 2022. One can observe a downward trend in resource consumption over time, notwithstanding short term fluctuations.

Note that DMC estimates apparent consumption in which production of waste and use of energy carriers are also part of consumption. Further, one should know that most biomass is used for food and not for substitution of abiotic materials. However, a distinction between the two types of flows cannot be made in the MFA.

Secondly, note that the MFA data are available only at macroeconomic level. Data on material use at sectoral level can be found in the Material Flow Monitor (MFM), with detailed physical supply and use tables of material flows, with data compatible to the National Accounts. ⁴⁾ However, this Monitor is only available from 2014 onwards (and bi-annual), ⁵⁾ whereas we aim to investigate longer term changes. More importantly, the material use by sector in the MFM is intermediate use by companies, or input of materials (products of other sectors) in the production process to produce new products (often material input for other sectors). This intermediate use cannot be added up over all sectors to a total at the macro-economic level. This would lead to double counting. There is no material use equivalent as for, say, value added in the National Accounts.

Finally, as mentioned above, we measure resource use with domestic material consumption (DMC). Annex A provides an alternative with domestic material input (DMI). DMI does not account for export, and is measured as extraction plus import. DMC is more easily compared between countries as exports are accounted for and there is no double counting of material flows. But the idea behind the application of the DMI indicator is that there is a more direct link with production with the use (input) of materials in this production. Unfortunately, the data in the MFA do not distinguish re-export flows in the import and export data.⁶⁾ Re-exports do not become part of the domestic production process but are goods that enter and leave the Netherlands without hardly any processing. With DMC, the re-exports are cancelled out by definition. Though we do not know the exact size of these re-exports for all years under consideration, from our Material Flow Monitor we know that about one third of total imports in 2022 are re-exports.

Recycling

Source: https://opendata.cbs.nl/statline/#/CBS/nl/dataset/83555NED/table?dl=2573B

Data on recycling is available from waste statistics. In the case that a country compiles waste accounts it is recommended to use these figures instead of the waste statistics reported to Eurostat, because waste accounts represent waste recycled within a country. Data on recycling in the Eurostat database comprises treatment of domestically generated waste. This means domestic generated waste that is treated abroad is also taken into account and, on the other hand, imported waste recycled domestically is excluded.

Biomass waste that is used for purposes of feed for animals (and not substitution of abiotic materials) should not be included. Recycled animal and vegetable waste can be omitted by assuming that most of it is used for animal feed. Due to a revision of the Dutch waste accounts we could not leave this waste category out and, therefore, it is included in our analysis. In the model, Total is Prim plus the amount of recycled (secondary) materials. Note that the original recycling source data are bi-annual data. To estimate the recycling amounts for the years without data points, we interpolated them by drawing straight lines between the adjacent years with data points. Figure 3.2 shows the amount of recycled materials (in megaton). We see a very slow upward trend. The largest increase occurred before 2000, thereafter the amounts fluctuate.

Economic activity

Source: https://opendata.cbs.nl/statline/#/CBS/nl/dataset/85865NED/table?dl=A9518

Data on economic activity come from the National Accounts. We apply GDP in market prizes estimated as chain linked volumes. Chain-linked level series are obtained by successively applying previous year's price's growth rates to the current price figure of a specific reference year, here 2021. Measured in constant prices of 2021, Dutch GDP increased from 553 billion euro in 1996 to 936 billion euro in 2022, an increase of 70 percent in 26 years.

Changes in the factors

Table 3.1 presents the values of the four factors at time points with 6 or 7 years interval in the period 1996-2022. This shows some of the dynamics in the data, though it does not show the fluctuations between the time points.

We see the share of primary abiotic resource consumption in total primary consumption decreases somewhat from 73 percent in 1996 to 67 percent in 2022, indicating substitution of abiotic materials for biotic materials. This occurs mainly after 2006. The recycling rate of the Netherlands is already very high, so there is rather little dynamism to be seen. The share of primary materials in total of primary and secondary (recycled) materials only slowly decreases over time, from 82 percent in 1996 to 77 percent in 2022.

Further, we can observe a clear trend in resource efficiency. The amount of materials used per unit value added decreased steadily over time from 0,42 kg per euro in 1996. to 0.25 kg per euro in 2022. The ratio however, is difficult to interpret, as it combines two elements which are different in nature. The total of resources consumed (numerator) remained relatively constant throughout time, while the economic activity (GDP, the denominator), increased strongly.

Estimation method

We applied an IDA estimation method developed by Delahaye et al. (2020). This calculates an average of the contribution of each factor in a year from a system of equations comprising variants which resemble each other very closely. In turn, this mathematical system is based on a decomposition approach by Dietzenbacher and Los (1998).⁷⁾ A main disadvantage of this method is that the number of equations increases quickly with the number of factors in the IDA. With four drivers we have 4! (faculteit) = 24 (non-unique) equations per driver to calculate the average contribution of the driver under consideration. We implemented the estimates in the programming language R. We refer to Delahaye et al. (2020, Annex) for a basis R script and more detail on their method. Our update of this basis R script and additional explanation is available on request.