Three months ended 

March 31,

2017

2016

amounts in millions

Fair Value Option Securities

$

30

24

Debt measured at fair value (a)

(116)

(3)

Change in fair value of bond hedges (b)

78

(28)

Other derivatives

(4)

(1)

$

(12)

(8)

(a)

Debt measured at fair value consists of the 2.25% Exchangeable Senior Debentures due 2046, the 1% Cash Convertible Notes due 2023 and the 1.375% Cash Convertible Notes due 2023, all as defined and discussed in note 10. Liberty elected to account for these instruments at fair value upon issuance. The 2.25% Exchangeable Senior Debentures due 2046, issued in August 2016, are marked to market based on the trading price of the underlying shares of Time Warner common stock and other observable market data as the significant inputs (Level 2). The 1% Cash Convertible Notes due 2023, issued in January 2017, are marked to market based on the trading price of the underlying shares of Series C Liberty Formula One common stock and other observable market data as the significant inputs (Level 2). The 1.375% Cash Convertible Notes due 2023, issued in October 2013, are marked to market based on the trading price of underlying basket of Series A Liberty SiriusXM, Liberty Braves and Liberty Formula One securities and other observable market data as the significant inputs (Level 2).