The Company’s authorized capital stock includes 250,000,000 shares of common stock, $0.01 par value per share. The following table summarizes the changes in the number of outstanding common units and shares of common stock:

	Common Shares
Balance, December 31, 2018		22,181,881
Issuance of common stock		—
Restricted stock units vested		412,938
Repurchase of common shares (1)		(120,163	)
Common stock repurchased and retired under share repurchase program		(169,400	)
Balance, June 30, 2019		22,305,256
Restricted stock units vested		38,181
Repurchase of common shares (1)		(9,427	)
Balance, August 5, 2019		22,334,010
Ratio to convert Amplify shares		0.933
Common stock issued to Legacy Amplify stockholders		20,837,633
Midstates stock outstanding and acquired with the Merger		20,415,005
Treasury shares acquired from the Merger		205,861
Restricted stock units vested		682,552
Repurchase of common shares (1)		(31,697	)
Common stock repurchased and retired under share repurchase program		(4,195,247	)
Cancelation and retirement of shares		(347,567	)
Balance, December 31, 2019		37,566,540
Issuance of common stock		—
Restricted stock units vested		132,237
Repurchase of common shares (1)		(35,268	)
Balance, December 31, 2020		37,663,509

In connection with the Merger, Legacy Amplify entered into a warrant agreement (the “Warrant Agreement”) with American Stock Transfer & Trust Company, LLC, as warrant agent (“AST”), pursuant to which Legacy Amplify issued warrants to purchase up to 2,173,913 shares of Legacy Amplify’s common stock (representing 8% of Legacy Amplify’s outstanding common stock as of the Effective Date including shares of Legacy Amplify’s common stock issuable upon full exercise of the warrants, but excluding any common stock issuable under the Legacy Amplify’s Management Incentive Plan), exercisable for a five year period commencing on the Effective Date at an exercise price of $42.60 per share.

The fair values for the warrants upon issuance on the Effective Date have been estimated using the Black-Scholes option pricing model using the following assumptions:

	Warrants Issued in
	Successor Period
Risk-free interest rate		2.06	%
Dividend yield		—
Expected life (in years)		5.0
Expected volatility		50.0	%
Strike Price	$	42.60
Calculated fair value	$	2.20

On the effective date of the Merger, Legacy Amplify, Midstates and AST entered into an Assignment and Assumption Agreement, pursuant to which the Company agreed to assume Legacy Amplify’s Warrant Agreement.

In connection with the Merger in August 2019, the Company assumed outstanding warrants of 4,647,520 Third Lien Notes Warrants at an exercise price of $22.78 per share (the “Third Lien Warrants”) and 2,332,089 Unsecured Creditor Warrants at an exercise price of $43.67 per share (the “Unsecured Creditor Warrants” and collectively with the Third Lien Warrants, the “Warrants”). The Warrants expired on April 21, 2020.

As of August 6, 2019, the Company assumed the outstanding treasury shares held by Midstates of 205,861 treasury shares outstanding. After the Merger closed, the Company retired and cancelled all treasury stock outstanding. No treasury stock remained outstanding at December 31, 2020 and 2019, respectively.

In connection, with the closing of the Merger, the board of directors approved the commencement of an open market share repurchase program of up to $25.0 million of the Company’s outstanding shares of common stock, with repurchases beginning on or after August 6, 2019. For the period from August 6, 2019 to December 31, 2019, the Company repurchased 4,195,247 shares of common stock at an average price of $6.28 per share for a total cost of approximately $24.9 million. The share repurchase program was terminated on December 31. 2019.

On December 21, 2018, Legacy Amplify’s board of directors authorized the repurchase of up to $25.0 million of Legacy Amplify’s outstanding shares of common stock, with repurchases to begin on or after January 9, 2019. During the six months ended June 30, 2019, Legacy Amplify repurchased 169,400 shares of common stock at an average price of $7.35 per share for a total cost of approximately $1.3 million. On April 18, 2019, in anticipation of the Merger, Legacy Amplify terminated the repurchase program.

On March 3, 2020, our board of directors approved a dividend of $0.10 per share of outstanding common stock or $3.8 million in aggregate, which was paid on March 30, 2020, to stockholders of record at the close of business on March 16, 2020. The board of directors subsequently suspended quarterly dividends. Future dividends, if any, are subject to debt covenants under our Revolving Credit Facility and discretionary approval by the board of directors.

On November 5, 2019, our board of directors approved a dividend of $0.20 per share of outstanding common stock or $7.7 million in aggregate, which was paid on December 18, 2019, to stockholders of record at the close of business on December 4, 2019.

On August 6, 2019, our board of directors approved a dividend of $0.20 per share of outstanding common stock or $8.2 million in aggregate, which was paid on September 18, 2019, to stockholders of record at the close of business on September 4, 2019.