Multivariate predictions do not work (as expected)

Summary:

In Multivariate predictions the target variable is predicted by one or more driver variables. Taking a simple example, I see that the target variable is not influenced by any driver.

Content (please ensure you mask any confidential information):

Multivariate predictions are part of the Advanced Predictions and use advanced statistical and machine learning algorithms that can improve your forecasting accuracy. The algorithms take the historical data for the variables included, as well as their what-if projections, to create a more accurate prediction of the target variable.

I prepared a followup blog post about Multivariate Forecasting. In this I wanted to provide a simple example on the functionality where 2 input drivers (IV_1 and IV_2) will predict the target variable (TV). The problem is, the input drivers do not alter the future data range of the target at all.