pre_text: 2 Investments in subsidiaries Investments are stated at cost less provisions for any impairment in value. Additions in the year relate to investments in Gestra Holdings Limited £1.6m and Spirax Sarco America Investments Limited £212.4m. Spirax Sarco America Investments Limited was incorporated on 24th October 2018 with the purpose of holding Group US$ investments and loans. Gestra Holdings Limited was incorporated on 9th October 2018 with the purpose of holding other Gestra Companies. Details relating to subsidiary undertakings are given on pages 207 to 211. Except where stated all classes of shares were 100% owned by the Group at 31st December 2019. The country of incorporation of the principal Group companies is the same as the country of operation with the exception of companies operating in the United Kingdom which are incorporated in Great Britain. All operate in steam, electrical thermal energy solutions, fluid path technologies or peristaltic pumping markets except those companies identified as a holding company on pages 207 to 211.
table: 2019 2018
table: £m £m
table: Cost:
table: At 1st January 445.8 269.4
table: Share options issued to subsidiary company employees 2.2 2.6
table: Additions 214.0 173.8
table: At 31st December 662.0 445.8
question: Analyse this data from a financial earnings document. What was the change in the cost at 31st December in 2019 from 2018?