Biogen Inc. (BIIB)

Marketable Debt Securities

Available-for-sale debt securities are recorded at fair market value and unrealized gains and losses are included in accumulated other comprehensive income (loss) in equity, net of related tax effects, unless the security has experienced a credit loss, Biogen has determined that Biogen has the intent to sell the security or Biogen has determined that it is more likely than not that Biogen will have to sell the security before its expected recovery. Realized gains and losses are reported in other income (expense), net, on a specific identification basis.

Marketable Equity Securities

Biogen’s marketable equity securities represent investments in publicly traded equity securities and are included in investments and other assets in the consolidated balance sheets. When assessing whether a decline in the fair value of a marketable equity security is other-than-temporary, Biogen considers the fair market value of the security, the duration of the security’s decline and prospects for the underlying business, including favorable or adverse clinical trial results, new product initiatives and new collaborative agreements with the companies in which Biogen has invested.

Source: 10-K (filing date: 2018-02-01).

Biogen Inc., adjustment to Net Income Attributable To Biogen Inc.

USD $ in thousands

	12 months ended	Dec 31, 2017	Dec 31, 2016	Dec 31, 2015	Dec 31, 2014	Dec 31, 2013
	Net income attributable to Biogen Inc. (as reported)
	Add: Unrealized gains (losses) on securities available for sale, net of tax
	Net income attributable to Biogen Inc. (adjusted)

Based on: 10-K (filing date: 2018-02-01), 10-K (filing date: 2017-02-02), 10-K (filing date: 2016-02-03), 10-K (filing date: 2015-02-04), 10-K (filing date: 2014-02-06).

Biogen Inc., adjusted ratios

		Dec 31, 2017	Dec 31, 2016	Dec 31, 2015	Dec 31, 2014	Dec 31, 2013
	Net Profit Margin
	Reported net profit margin
	Adjusted net profit margin
	Return on Equity (ROE)
	Reported ROE
	Adjusted ROE
	Return on Assets (ROA)
	Reported ROA
	Adjusted ROA

Based on: 10-K (filing date: 2018-02-01), 10-K (filing date: 2017-02-02), 10-K (filing date: 2016-02-03), 10-K (filing date: 2015-02-04), 10-K (filing date: 2014-02-06).

Biogen Inc., Ratios: Reported vs. Adjusted

		Dec 31, 2017	Dec 31, 2016	Dec 31, 2015	Dec 31, 2014	Dec 31, 2013
	As Reported
	Selected Financial Data (USD $ in thousands)
	Net income attributable to Biogen Inc.
	Revenues
	Ratio
	Net profit margin1
	Adjusted: Mark to Market Available-for-sale Securities
	Selected Financial Data (USD $ in thousands)
	Adjusted net income attributable to Biogen Inc.
	Revenues
	Ratio
	Adjusted net profit margin2

Based on: 10-K (filing date: 2018-02-01), 10-K (filing date: 2017-02-02), 10-K (filing date: 2016-02-03), 10-K (filing date: 2015-02-04), 10-K (filing date: 2014-02-06).

2017 Calculations

		Dec 31, 2017	Dec 31, 2016	Dec 31, 2015	Dec 31, 2014	Dec 31, 2013
	As Reported
	Selected Financial Data (USD $ in thousands)
	Net income attributable to Biogen Inc.
	Total Biogen Inc. shareholders’ equity
	Ratio
	ROE1
	Adjusted: Mark to Market Available-for-sale Securities
	Selected Financial Data (USD $ in thousands)
	Adjusted net income attributable to Biogen Inc.
	Total Biogen Inc. shareholders’ equity
	Ratio
	Adjusted ROE2

Based on: 10-K (filing date: 2018-02-01), 10-K (filing date: 2017-02-02), 10-K (filing date: 2016-02-03), 10-K (filing date: 2015-02-04), 10-K (filing date: 2014-02-06).

2017 Calculations

		Dec 31, 2017	Dec 31, 2016	Dec 31, 2015	Dec 31, 2014	Dec 31, 2013
	As Reported
	Selected Financial Data (USD $ in thousands)
	Net income attributable to Biogen Inc.
	Total assets
	Ratio
	ROA1
	Adjusted: Mark to Market Available-for-sale Securities
	Selected Financial Data (USD $ in thousands)
	Adjusted net income attributable to Biogen Inc.
	Total assets
	Ratio
	Adjusted ROA2

Based on: 10-K (filing date: 2018-02-01), 10-K (filing date: 2017-02-02), 10-K (filing date: 2016-02-03), 10-K (filing date: 2015-02-04), 10-K (filing date: 2014-02-06).

2017 Calculations