Please answer the given financial question based on the context.
Context: the table below presents the estimated maximum potential var arising from a one-day loss in fair value for our interest rate , foreign currency , commodity , and equity market-risk-sensitive instruments outstanding as of may 26 , 2019 and may 27 , 2018 , and the average fair value impact during the year ended may 26 , 2019. .
|in millions|fair value impact may 26 2019|fair value impact averageduringfiscal 2019|fair value impact may 27 2018|
|interest rate instruments|$ 74.4|$ 46.1|$ 33.2|
|foreign currency instruments|16.8|19.0|21.3|
|commodity instruments|4.1|2.5|1.9|
|equity instruments|2.3|2.2|2.0|
.
Question: what is the change in fair value of foreign currency instruments from 2018 to 2019?


Answer: The answer is:-4.5