Monte Carlo - Historical Data required?

[Cipher2014]

Hi David,

I remember in one of your videos you mentioned that there are 3 approaches to VaR

Historical - historical data
Monte Carlo - future data
Parametric - no data

My question is: for MC, the first step is to generate price paths using GBM. For that, while e is randomized, don't we need historical data to come up with the mean(drift) and variance(shock)?

Could you kindly clarify?

Thanks,
Ying