Yield measures the income as a percentage of the security price or the face value of an asset for a period of time, which is often for a year (annual or yearly). 


A stock (the security here) was bought for a spot price of Rs 300 a share, with company-paid dividend worth Rs 15 on each share. Its price increased by Rs 10, ie. each share now costs Rs 310. The yield of the shareholder would then be 8.33 percent [{(15+10)/300}*100].

Know more 

Yield may include income from different sources such as dividend income and share price appreciation.