4. Revenue
4.1 Disaggregation of revenue
 
    Company
    31 March
2021
Rm

31 March
2020
Rm
Revenue 39 220 39 251
Revenue from contracts with customers recognised over time 36 246 36 224
  Voice 10 840 12 850
  Interconnection 920 956
  Data 21 731 18 906
  Information technology 1 460 2 039
  Customer premises equipment related services1 1 055 1 194
  Interest revenue 240 279
Revenue from contracts with customers recognised at a point in time 2 873 2 917
  Customer premises equipment 2 742 2 750
  Sundry revenue 131 167
Lease revenue2 101 110
1 Certain information technology hardware and software items and customer premises equipment related services were incorrectly reflected at a point in time and has now been moved to revenue over time. The comparatives have been re-presented. Refer to note 2.4.7.6 for the significant judgements regarding the CPE related services revenue.
2 In the current year, it was identified that lease revenue was incorrectly included in sundry revenue and has now been moved to a separate line item, "lease revenue". The comparatives have been restated.

Refer to note 3 for the disaggregated revenue per segment for the Group.

Included in Telkom Company revenue is revenue, to the value of R7 157 million (31 March 2020: R9 471 million), which relates to Enterprise customer contracts which were sold to BCX in previous financial years, which have been retained in the name of Telkom SA SOC Ltd. Refer to note 2.4.7.5 for the significant judgements and estimates considered in determining that Telkom is the principal in relation to these transactions.

4.2 Transaction price allocated to the remaining performance obligations
 

The tables below include revenue expected to be recognised in the future, related to performance obligations that are unsatisfied (or partially unsatisfied) at the reporting date.

  Group
31 March 2021
  2022
Rm
2023
Rm
Beyond
2024

Rm
Voice 431 148 14
Data 2 347 779 50
Information technology 125 8
  31 March 2020
  2021
Rm
2022
Rm
Beyond 2023
Rm
Voice 439 131 7
Data 2 752 973 111
Information technology 158 23
  Company
31 March 2021
  2022
Rm
2023
Rm
Beyond
2024
Rm
Voice 431 148 14
Data 2 347 779 50
  31 March 2020
  2021
Rm
2022
Rm
Beyond 2023
Rm
Voice 439 131 7
Data 2 752 973 111

All revenue from contracts with customers is included in the amounts presented above.

The Group and Company apply the practical expedient in paragraph 121 of IFRS 15 and do not disclose information about remaining performance obligations that have original expected durations of one year or less.

4.3 Customer relationship periods
 

The customer relationship periods (CRP) in the current financial year are determined as follows:

  • Voice revenue: 5.5 years (31 March 2020: 5 to 6.5 years)
  • Wholesale revenue: 4 years (31 March 2020: 4 years)
  • Non-voice revenue: 3.5 years (31 March 2020: 4 to 5.5 years)

The average CRP in respect of non-voice changed from 4 to 5.5 years as at March 2020 to 3.5 years as at March 2021. The voice CRP changed from 5 to 6.5 years as at March 2020 to 5.5 years as at March 2021. This is a change in an accounting estimate in terms of IAS 8 and accounted for prospectively. The change in the non-voice CRP resulted in an accelerated rate of deferred installation revenue recognition with the effect being an increase in revenue of R28 million in the 2021 financial year. The change in the voice CRP resulted in a decelerated rate of deferred installation revenue recognition with the effect being a decrease in revenue of R1.4 million in the 2021 financial year. Revenue recognition in respect of deferred installation fees for the future periods is expected to decrease by R26.6 million (31 March 2020: R32 million) due to these changes in accounting estimates.

4.4 Impact of COVID–19 on revenue
 

There was no significant impact of COVID-19 on Mobile revenue as the telecommunications industry was declared as an essential service in South Africa, which allowed the Group to continue to connect South Africans during the national lockdown period. This contributed to the Group experiencing a surge in fixed and mobile network traffic for telco services from people working from home. There were no significant contract modifications that took place and both new and existing contracts were assessed to be enforceable at the end of the reporting date.

Telkom enhanced broadband-led propositions across customer segments and scaled up digital platforms as the Telkom stores were closed during the early phase of the national lockdown. As a result, the Mobile business sustained its growth trajectory into the first half of the year, driven by data demand.

The Group’s fixed and IT services revenue has however been negatively impacted by COVID-19 during the period under review. To curb the revenue decline in fixed line, Telkom has been migrating its fixed line customers to fibre and wireless from copper-based technology.