13.5. Revenue from contracts with customers by date of transfer
| NOTE | Refining Segment |
Petrochemical Segment | Energy Segment | Retail Segment |
Upstream Segment | Corporate Functions | Total | ||||||||
| 2021 | 2020 | 2021 | 2020 | 2021 | 2020 | 2021 | 2020 | 2021 | 2020 | 2021 | 2020 | 2021 | 2020 | ||
| At a point in time | 44 520 | 26 401 | 9 465 | 6 486 | 94 | 29 | 30 651 | 23 116 | – | – | 372 | 27 | 85 102 | 56 059 | |
| Over time | 12 429 | 7 672 | 6 538 | 4 094 | 15 911 | 10 062 | 10 194 | 7 508 | 797 | 482 | 48 | 38 | 45 917 | 29 856 | |
| 56 949 | 34 073 | 16 003 | 10 580 | 16 005 | 10 091 | 40 845 | 30 624 | 797 | 482 | 420 | 65 | 131 019 | 85 915 | ||
As part of the Refining and Petrochemical segments, with respect to sales of petrochemical and refinery products, the Group recognises revenue from the fulfilment of the performance obligation, depending on the terms of delivery applied (Incoterms CFR, CIF, CPT).
In case of some deliveries, the Group as a seller is obliged to organize transport. When the control of good transferred to the customer before the transport service is completed, the delivery of goods and transport becomes separate performance obligations. The delivery of goods is an obligation satisfied at a point in time, while transport is a continuous obligation (satisfied over time), where the customer simultaneously receives and consumes benefits from the service. Revenues are recognised on the basis of the output method with respect to the rendered services.
In the Retail segment, the moment of fulfilment of the performance obligation is the moment of transfer of good, except for sales of fuels in the Fleet Program using Fleet Cards.
Revenue recognised over time mainly relate to the sale of electricity and energy distribution services within the Energy segment, fuel sales in the Fleet Programme and subscription sale within Retail segment and the sale of gas and crude oil within the Upstream segment. These revenues are recognised using the output method for the delivered units of goods.