# Transaction footprint calculation
source: https://developer.mastercard.com/carbon-calculator-china/documentation/use-cases/transaction-footprint-calculation/index.md

## Overview {#overview}

The file-based scoring calculation service enables issuers to assess transaction footprints based on the customers' payment activity made using Mastercard cards. This service does not require the issuer or the cardholder to register payment cards.

## Sequence diagram {#sequence-diagram}

Diagram tran-ftprnt-calc

## How to calculate the transaction footprint? {#how-to-calculate-the-transaction-footprint}

The process that Carbon Calculator follows to generate the carbon scores is listed in the following steps:

1. The Carbon Calculator application picks up all the cleared transactions from the previous day of a given BIN to generate the carbon score. For example, if the application runs on 30 January at 1 AM, it would retrieve all the transactions cleared on 29 January.
2. It generates a CSV file with a maximum 100,000 scored records. If the records exceed 100,000, the scheduler creates a new file.
3. If no transactions are found for the previous day, the application sends an empty CSV file.
4. The application can upload up to a maximum of 5000 files in a day to [NGFT](https://developer.mastercard.com/carbon-calculator-china/documentation/file-based-scoring-protocols/ngft_file_based_scoring/index.md) or [GFT](https://developer.mastercard.com/carbon-calculator-china/documentation/file-based-scoring-protocols/gft_file_based_scoring/index.md).
5. The scored CSV file is transferred to the issuer daily.

## Next steps {#next-steps}

For more details on the scored CSV file format and error codes, refer to the [File Reference and Error Codes](https://developer.mastercard.com/carbon-calculator-china/documentation/file-reference-error-codes/index.md) section.