In order to measure risk practically, in 1952 Markowitz put forward using the variance of return rate as risk measure index based on the definition of risk which is the uncertainty or fluctuation.

• 为了在实际中定量测度风险，1952年，Markowitz基于“风险为收益率的不确定性或易变性”的概念，提出以证券收益率的方差作为风险计量指标，开创了定量化计量风险的先河。