the conversion takes place. The value of the RSUs, when converted into cash, will be equivalent to the difference between  the market price of equivalent number of common shares at the time the conversion takes place and the market price on the date  the RSUs are granted. The company uses equity derivative contracts to offset its exposure to the change in share prices in respect  of vested and unvested DSUs and RSUs. The fair value of the vested DSUs and RSUs as at December 31, 2013 was $508 million  (2012 – $436 million). Employee compensation expense for these plans is charged against income over the vesting period of the DSUs and RSUs.  The amount payable by the company in respect of vested DSUs and RSUs changes as a result of dividends and share price  movements. All of the amounts attributable to changes in the amounts payable by the company are recorded as employee  compensation expense in the period of the change, and for the year ended December 31, 2013, including those of operating  subsidiaries, totalled $19 million (2012 – $8 million), net of the impact of hedging arrangements. The change in the number of DSUs and RSUs during 2013 and 2012 was as follows: The following table summarizes revenue and other gains for 2013 and 2012: The fair value of DSUs is equal to the traded price of the company’s common shares. The fair value of RSUs was determined using the Black-Scholes model of valuation with inputs to the model as follows: 22.  REVENUES AND OTHER GAINS DSUs RSUs Number of Units  (000’s) Number of Units  (000’s) Weighted  Average  Exercise Price Outstanding at January 1, 2013  7,447 8,030 C$ 13.56 Granted and reinvested  1,830 — — Exercised and cancelled  (206) (750) 12.76 Outstanding at December 31, 2013  9,071 7,280 C$ 13.64 DSUs RSUs Number of Units  (000’s) Number of Units  (000’s) Weighted  Average  Exercise Price Outstanding at January 1, 2012  7,255 8,030 C$ 13.56 Granted and reinvested  430 — — Exercised and cancelled  (238) — — Outstanding at December 31, 2012  7,447 8,030 C$ 13.56 Unit Dec. 31, 2013 Dec. 31, 2012 Share price on date of measurement  C$ 41.22 36.44 Weighted average exercise price  C$ 13.64 13.56 Term to exercise  Years 8.2 9.2 Share price volatility  % 23.35 24.11 Weighted average of expected annual dividend yield  % 2.4 1.4 Risk-free rate  % 3.0 2.2 Weighted average fair value of a unit  C$ 24.18 21.47 YEARS ENDED DECEMBER 31 (MILLIONS) 2013 2012 Revenues  $ 20,093 $ 18,696 Other gains  737 70 $ 20,830 $ 18,766 Revenues include $12,834 million (2012 – $12,511 million) from the sale of goods, $6,448 million (2012 – $5,764 million) from  the rendering of services, of which $558 million (2012 – $nil) was earned in our asset management segment and received in kind,  and $811 million (2012 – $421 million) from other activities.  2013 ANNUAL REPORT 137