CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities
Net income	$ 1,768.7	$ 1,581.2	$ 1,254.0
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization of property and equipment	159.5	143.6	133.4
Stock-based compensation expense	197.1	152.0	161.6
Realized gains on dispositions of available-for-sale T. Rowe Price investment products		(83.1)	(53.0)
Gains recognized upon transfer of an investment in a T. Rowe Price mutual fund from available-for-sale to held as trading		(23.6)	0.0
Net gains recognized on other investments	(50.5)	(49.7)	(31.0)
Net investments in T. Rowe Price investment products to economically hedge supplemental savings plan liability	(129.5)	(218.6)	0.0
Net change in trading securities held by consolidated T. Rowe Price investment products	(437.0)	(1,492.9)	(1,297.9)
Changes in accounts receivable and accrued revenue	12.7	(101.6)	(10.5)
Changes in payables and accrued liabilities	111.3	323.4	139.2
Other changes in assets and liabilities	(12.4)	(1.2)	(125.3)
Net cash provided by operating activities	1,619.9	229.5	170.5
Cash flows from investing activities
Purchases of T. Rowe Price investment products	(1,124.0)	(39.9)	(0.3)
Dispositions T. Rowe Price investment products	352.4	336.6	219.1
Net cash of T. Rowe Price investment products on consolidation (deconsolidation)	(23.8)	(64.2)	41.4
Additions to property and equipment	(168.5)	(186.1)	(148.3)
Other investing activity	88.4	(7.4)	(5.7)
Net cash provided by (used in) investing activities	(875.5)	39.0	106.2
Cash flows from financing activities
Repurchases of common stock	(1,090.4)	(458.1)	(676.9)
Common share issuances under stock-based compensation plans	74.8	201.1	126.3
Dividends paid to common stock and equity-award holders	(694.3)	(563.1)	(540.8)
Net subscriptions received from redeemable non-controlling interest holders	470.4	1,281.6	915.0
Net cash provided by (used in) provided by financing activities	(1,239.5)	461.5	(176.4)
Effect of exchange rate changes on cash and cash equivalents of consolidated T. Rowe Price investment products	(15.4)	5.3	(2.1)
Net change in cash and cash equivalents during period	(510.5)	735.3	98.2
Cash and cash equivalents at beginning of period, including $103.1 million at December 31, 2017 and $65.6 million at December 31, 2016 held by consolidated T. Rowe Price investment products	2,005.8	1,270.5	1,172.3
Cash and cash equivalents at end of period, including $70.1 million at December 31, 2018, $103.1 million at December 31, 2017, and $65.6 million at December 31, 2016, held by consolidated T. Rowe Price investment products	$ 1,495.3	$ 2,005.8	$ 1,270.5

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Net Gains (Losses) Recognized on Investments

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