note 6 : inventories we use the last-in , first-out ( lifo ) method for the majority of our inventories located in the continental u.s . other inventories are valued by the first-in , first-out ( fifo ) method . fifo cost approximates current replacement cost . inventories measured using lifo must be valued at the lower of cost or market . inventories measured using fifo must be valued at the lower of cost or net realizable value . inventories at december 31 consisted of the following: .

2018: finished products: 988.1
work in process: 2628.2
raw materials and supplies: 506.5
total ( approximates replacement cost ): 4122.8
increase ( reduction ) to lifo cost: -11
inventories: 4111.8
2017: finished products: 1211.4
work in process: 2697.7
raw materials and supplies: 488.8
total ( approximates replacement cost ): 4397.9
increase ( reduction ) to lifo cost: 60.4
inventories: 4458.3

inventories valued under the lifo method comprised $ 1.57 billion and $ 1.56 billion of total inventories at december 31 , 2018 and 2017 , respectively . note 7 : financial instruments financial instruments that potentially subject us to credit risk consist principally of trade receivables and interest- bearing investments . wholesale distributors of life-science products account for a substantial portion of our trade receivables ; collateral is generally not required . we seek to mitigate the risk associated with this concentration through our ongoing credit-review procedures and insurance . a large portion of our cash is held by a few major financial institutions . we monitor our exposures with these institutions and do not expect any of these institutions to fail to meet their obligations . major financial institutions represent the largest component of our investments in corporate debt securities . in accordance with documented corporate risk-management policies , we monitor the amount of credit exposure to any one financial institution or corporate issuer . we are exposed to credit-related losses in the event of nonperformance by counterparties to risk-management instruments but do not expect any counterparties to fail to meet their obligations given their high credit ratings . we consider all highly liquid investments with a maturity of three months or less from the date of purchase to be cash equivalents . the cost of these investments approximates fair value . our equity investments are accounted for using three different methods depending on the type of equity investment : 2022 investments in companies over which we have significant influence but not a controlling interest are accounted for using the equity method , with our share of earnings or losses reported in other-net , ( income ) expense . 2022 for equity investments that do not have readily determinable fair values , we measure these investments at cost , less any impairment , plus or minus changes resulting from observable price changes in orderly transactions for the identical or similar investment of the same issuer . any change in recorded value is recorded in other-net , ( income ) expense . 2022 our public equity investments are measured and carried at fair value . any change in fair value is recognized in other-net , ( income ) expense . we review equity investments other than public equity investments for indications of impairment on a regular basis . our derivative activities are initiated within the guidelines of documented corporate risk-management policies and are intended to offset losses and gains on the assets , liabilities , and transactions being hedged . management reviews the correlation and effectiveness of our derivatives on a quarterly basis. .

Questions:
what was the total in raw materials and supplies in 2018?
and what was it in 2017?
what was, then, the change over the year?
what was the total in raw materials and supplies in 2017?
and how much does that change represent in relation to this 2017 total, in percentage?

Answers:
506.5
488.8
17.7
488.8
4%