The Time Series Method, which are used for forecasts in supply chains, is based on the assumption that:

Historical patterns of demand are a good indicator of future demand. In time series analysis it is the fundamental assumption that future forecast is based on past, historical value of the same variable. Historical variable will extend to the future in a pattern or trend. Here variable is time-period only. From the given statement's only this is the only assumption we can make. In time series analysis competitor's opening new store won't impact the result because it rely on historical data and any particular environmental factor has also no role.

Explain the above mentioned statements with reference to the Time Series Method ??