Think of an example of parametric estimating in your personal experience, such as the use of a cost multiplier based on a similar, past cost. Did parametric estimating work or not. Discuss the reason...

Think of an example of parametric estimating in your personal experience,

such as the use of a cost multiplier based on a similar, past cost. Did parametric estimating work or not. Discuss the reason why. ans should be around 300 to 500 words any idea or suggestion?