The following table provides the securities activity within the decommissioning and SNF trusts: The base cost of fixed income securities was $1.1 billion and $1.1 billion as of December 31, 2020 and 2019, respectively. The base cost of equity securities was $654 million and $623 million as of December 31, 2020 and 2019, respectively. The fair value of fixed income securities held in the nuclear trust funds, summarized by contractual maturities, as of December 31, 2020 was as follows: Years Ended December 31, 2020 2019 2018 (in millions) Proceeds from Investment Sales $ 1,593.4  $ 1,473.0  $ 2,010.0  Purchases of Investments 1,637.2  1,531.0  2,064.7  Gross Realized Gains on Investment Sales 26.4  76.5  47.5  Gross Realized Losses on Investment Sales 26.1  24.3  32.8  Fair Value of Fixed Income Securities (in millions) Within 1 year $ 294.8  After 1 year through 5 years 371.3  After 5 years through 10 years 214.4  After 10 years 345.7  Total $ 1,226.2  337