Share-Based Payment (Tables)

12 Months Ended

Dec. 31, 2019

Share-based Payment

Fair Value Measurement of Equity-Settled Share Options

	Year ended December 31,
	2019		2018		2017
Dividend yield (%)		0		0		0
Expected volatility of the share prices (%)		78%-84%		93%-95%		89%-94%
Risk-free interest rate (%)		1.92-2.63		2.63-2.88		1.76-2.4

Stock Option Activity

	2019				2018
	Number of options		Weighted average exercise price		Number of options		Weighted average exercise price
			USD				USD
Outstanding at beginning of year		3,197,616		3.07		2,467,023		2.28
Granted during the year		790,300		8.82		751,977		5.60
Expired during the year		39,094		5.21		2,000		6.00
Exercised during the year		480,878		0.27		9,692		0.25
Forfeited during the year		62,756		6.16		9,692		0.25
Share options outstanding at end of year		3,405,188		4.76		3,197,616		3.07
Share options exercisable at end of year		1,865,572		2.68		1,705,256		1.21