The calculations of basic and diluted income per share attributable to CBRE Group, Inc. shareholders are as follows (dollars in thousands, except share data):

	Three Months Ended March 31,
	2020		2019
Basic Income Per Share
Net income attributable to CBRE Group, Inc. shareholders	$	172,195	$	164,409
Weighted average shares outstanding for basic income per share		334,969,826		336,020,431
Basic income per share attributable to CBRE Group, Inc. shareholders	$	0.51	$	0.49
Diluted Income Per Share
Net income attributable to CBRE Group, Inc. shareholders	$	172,195	$	164,409
Weighted average shares outstanding for basic income per share:		334,969,826		336,020,431
Dilutive effect of contingently issuable shares		4,768,085		4,137,968
Weighted average shares outstanding for diluted income per share		339,737,911		340,158,399
Diluted income per share attributable to CBRE Group, Inc. shareholders	$	0.51	$	0.48

For the three months ended March 31, 2020 and 2019, 341,359 and 547,676, respectively, of contingently issuable shares were excluded from the computation of diluted income per share because their inclusion would have had an anti-dilutive effect.

In October 2016, our board of directors authorized the company to repurchase up to an aggregate of $250.0 million of our Class A common stock over three years. During January 2019, through an existing stock repurchase plan entered into pursuant to Rule 10b5-1 under the Exchange Act (10b5-1 plan), we spent $45.1 million to repurchase 1,144,449 shares of our Class A common stock with an average price paid per share of $39.38.

In February 2019, our board of directors authorized a new program for the company to repurchase up to $300.0 million of our Class A common stock over three years, effective March 11, 2019. The previous program terminated upon the effectiveness of the new stock repurchase program. In each of August and November 2019, our board of directors authorized an additional $100.0 million under our new program, bringing the total authorized amount under the new program to a total of $500.0 million. During the year ended December 31, 2019, under the March 2019 program, and through repurchases under a 10b5-1 plan, we spent $100.0 million to repurchase an additional 1,936,458 shares of our Class A common stock with an average price paid per share of $51.64. During the month of March 2020, through repurchases under a 10b5-1 plan, we spent $50.0 million to repurchase an additional 1,050,084 shares of our Class A common stock with an average price paid per share of $47.62. As of March 31, 2020, we had $350.0 million of capacity remaining under our current stock repurchase program.