Deferred income

x 1 million

2019

2018

Book value at 1 January

648

554

Customer construction contributions received

96

112

Income recognised

-19

-18

Book value at 31 December

725

648

Classification

2019

2018

Current

18

16

Non-current

707

632

Total

725

648

The short-term deferred income is reported under 'contract liabilities' in 'Trade and other liabilities'.