Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

Share based compensation

Share-Based compensation expense

($ millions)	2017	2016
Equity-settled plans	48	48
Cash-settled plans	334	395
Total share-based compensation expense	382	443

Summary of liability recognized for share-based compensation

($ millions)	2017	2016
Current Liability	344	359
Long-Term Liability (note 23)	361	364
Total Liability	705	723

Weighted average fair value of options granted during the period and the weighted average assumptions used in their determination

	2017	2016
Annual dividend per share	$ 1.28	$ 1.16
Risk-free interest rate	1.09%	0.55%
Expected life	5 years	5 years
Expected volatility	25%	28%
Weighted average fair value per option	$ 6.42	$ 4.60

Summary of stock option plans

	2017			2016
	Number (thousands)		Weighted Average Exercise Price ($)	Number (thousands)		Weighted Average Exercise Price ($)
Outstanding, beginning of year	31 442		35.98	29 090		36.97
Granted	7 401		42.04	8 145		30.26
Exercised for cash payment	(6	)	32.00	(1 441	)	30.39
Exercised as options for common shares	(6 223	)	36.65	(3 983	)	33.36
Forfeited/expired	(1 504	)	42.21	(369	)	38.12
Outstanding, end of year	31 110		36.96	31 442		35.98
Exercisable, end of year	17 363		36.53	17 821		37.74

Exercise price ranges and weighted average remaining contractual lives

For the options outstanding at December 31, 2017, the exercise price ranges and weighted average remaining contractual lives are shown below:

	Outstanding			Exercisable
Exercise Prices ($)	Number (thousands)	Weighted Average Remaining Contractual Life (years)	Weighted Average exercise price ($)	Number (thousands)	Weighted Average exercise price ($)
24.50-34.99	11 466	4	31.32	6 714	32.07
35.00-39.99	9 987	4	37.72	8 006	37.44
40.00-44.99	8 347	5	41.99	1 333	41.70
45.00-49.99	1 197	0	47.52	1 197	47.52
50.00-69.97	113	0	59.54	113	59.54
Total	31 110	4	36.96	17 363	36.53

Summary of common shares available for granting future options

(thousands)	2017	2016
	28 972	10 937

Summary of share units and stock appreciation rights

(thousands)		PSU		RSU		DSU
Outstanding, December 31, 2015		2 465		19 104		1 072
	Granted	1 683		6 194		186
	Redeemed for cash	(1 714	)	(6 649	)	(40	)
	Forfeited/expired	(21	)	(491	)	—
Outstanding, December 31, 2016		2 413		18 158		1 218
	Granted	1 570		5 009		202
	Redeemed for cash	(1 663	)	(6 354	)	(118	)
	Forfeited/expired	(53	)	(741	)	—
Outstanding, December 31, 2017		2 267		16 072		1 302

Stock Appreciation Rights (SARs)

Share based compensation

Summary of share units and stock appreciation rights

	2017			2016
	Number (thousands)		Weighted Average Exercise Price ($)	Number (thousands)		Weighted Average Exercise Price ($)
Outstanding, beginning of year	485		34.90	957		27.98
Granted	107		42.05	142		30.23
Exercised	(176	)	35.59	(610	)	23.07
Forfeited/expired	(29	)	37.32	(4	)	19.44
Outstanding, end of year	387		36.38	485		34.90
Exercisable, end of year	162		35.39	240		36.29