pre_text: Exposures The maximum credit risk exposure of the group’s financial assets at the balance sheet date is as follows: The carrying amount excludes £445m (2017/18: £317m, 2016/17: £360m) of non-current trade and other receivables which relate to non-financial assets, and £1,456m (2017/18: £1,496m, 2016/17: £1,106m) of prepayments, deferred contract costs and other receivables.
table: Notes 2019 2018 2017
table: At 31 March Notes £m £m £m
table: Derivative financial assets 1,592 1,509 2,246
table: Investments 23 3,268 3,075 1,564
table: Trade and other receivables a 17 1,766 2,518 2,729
table: Contract assets 6 1,602 – –
table: Cash and cash equivalents 24 1,666 528 528
table: 9,894 7,630 7,067
question: Analyse this data from a financial earnings document. What is the change in the Derivative financial assets from 2018 to 2019?